all: change optional to result of io (#16075)

cmd/tools/check_os_api_parity.v

@@ -43,7 +43,7 @@ fn main() {
 	vexe := pref.vexe_path()
 	vroot := os.dir(vexe)
 	util.set_vroot_folder(vroot)
-	os.chdir(vroot)?
+	os.chdir(vroot)!
 	cmd := diff.find_working_diff_command() or { '' }
 	mut app := App{
 		diff_cmd: cmd

cmd/tools/fast/fast.v

@@ -15,7 +15,7 @@ const vdir = @VEXEROOT
 fn main() {
 	dump(fast_dir)
 	dump(vdir)
-	os.chdir(fast_dir)?
+	os.chdir(fast_dir)!
 	if !os.exists('$vdir/v') && !os.is_dir('$vdir/vlib') {
 		println('fast.html generator needs to be located in `v/cmd/tools/fast`')
 	}
@@ -32,11 +32,11 @@ fn main() {
 	// fetch the last commit's hash
 	commit := exec('git rev-parse HEAD')[..8]
 	if !os.exists('table.html') {
-		os.create('table.html')?
+		os.create('table.html')!
 	}
-	mut table := os.read_file('table.html')?
+	mut table := os.read_file('table.html')!
 	if os.exists('website/index.html') {
-		uploaded_index := os.read_file('website/index.html')?
+		uploaded_index := os.read_file('website/index.html')!
 		if uploaded_index.contains('>$commit<') {
 			println('nothing to benchmark')
 			exit(1)
@@ -48,7 +48,7 @@ fn main() {
 
 	// build an optimized V
 	println('  Building vprod...')
-	os.chdir(vdir)?
+	os.chdir(vdir)!
 	if os.args.contains('-noprod') {
 		exec('./v -o vprod cmd/v') // for faster debugging
 	} else {
@@ -82,8 +82,8 @@ fn main() {
 	commit_date := exec('git log -n1 --pretty="format:%at" $commit')
 	date := time.unix(commit_date.int())
 
-	os.chdir(fast_dir)?
-	mut out := os.create('table.html')?
+	os.chdir(fast_dir)!
+	mut out := os.create('table.html')!
 
 	// place the new row on top
 	html_message := message.replace_each(['<', '&lt;', '>', '&gt;'])
@@ -105,25 +105,25 @@ fn main() {
 		<td>${int(f64(vlines) / f64(diff1) * 1000.0)}</td>
 	</tr>\n' +
 		table.trim_space()
-	out.writeln(table)?
+	out.writeln(table)!
 	out.close()
 
 	// regenerate index.html
-	header := os.read_file('header.html')?
-	footer := os.read_file('footer.html')?
-	mut res := os.create('index.html')?
-	res.writeln(header)?
-	res.writeln(table)?
-	res.writeln(footer)?
+	header := os.read_file('header.html')!
+	footer := os.read_file('footer.html')!
+	mut res := os.create('index.html')!
+	res.writeln(header)!
+	res.writeln(table)!
+	res.writeln(footer)!
 	res.close()
 
 	// upload the result to github pages
 	if os.args.contains('-upload') {
 		println('uploading...')
-		os.chdir('website')?
+		os.chdir('website')!
 		os.execute_or_exit('git checkout gh-pages')
-		os.cp('../index.html', 'index.html')?
-		os.rm('../index.html')?
+		os.cp('../index.html', 'index.html')!
+		os.rm('../index.html')!
 		os.system('git commit -am "update benchmark"')
 		os.system('git push origin gh-pages')
 	}

cmd/tools/measure/scanner_speed.v

@@ -7,14 +7,14 @@ fn main() {
 	files := os.args#[1..]
 	if files.len > 0 && files[0].starts_with('@') {
 		lst_path := files[0].all_after('@')
-		listed_files := os.read_file(lst_path)?.split('\n')
-		process_files(listed_files)?
+		listed_files := os.read_file(lst_path)!.split('\n')
+		process_files(listed_files)!
 		return
 	}
-	process_files(files)?
+	process_files(files)!
 }
 
-fn process_files(files []string) ? {
+fn process_files(files []string) ! {
 	mut pref := pref.new_preferences()
 	pref.is_fmt = true
 	pref.skip_warnings = true
@@ -31,7 +31,7 @@ fn process_files(files []string) ? {
 			continue
 		}
 		sw.restart()
-		s := scanner.new_scanner_file(f, .skip_comments, pref)?
+		s := scanner.new_scanner_file(f, .skip_comments, pref)!
 		f_us := sw.elapsed().microseconds()
 		total_us += f_us
 		total_bytes += s.text.len

cmd/tools/oldv.v

@@ -125,7 +125,7 @@ fn main() {
 	should_sync := fp.bool('cache-sync', `s`, false, 'Update the local cache')
 	context.is_bisect = fp.bool('bisect', `b`, false, 'Bisect mode. Use the current commit in the repo where oldv is.')
 	if !should_sync && !context.is_bisect {
-		fp.limit_free_args(1, 1)?
+		fp.limit_free_args(1, 1)!
 	}
 	////
 	context.cleanup = fp.bool('clean', 0, false, 'Clean before running (slower).')

cmd/tools/performance_compare.v

@@ -194,7 +194,7 @@ fn main() {
 	fp.description(tool_description)
 	fp.arguments_description('COMMIT_BEFORE [COMMIT_AFTER]')
 	fp.skip_executable()
-	fp.limit_free_args(1, 2)?
+	fp.limit_free_args(1, 2)!
 	context.vflags = fp.string('vflags', 0, '', 'Additional options to pass to the v commands, for example "-cc tcc"')
 	context.hyperfineopts = fp.string('hyperfine_options', 0, '', 'Additional options passed to hyperfine.
 ${flag.space}For example on linux, you may want to pass:

cmd/tools/repeat.v

@@ -143,19 +143,19 @@ const (
 
 fn main() {
 	mut context := Context{}
-	context.parse_options()?
+	context.parse_options()!
 	context.run()
 	context.show_diff_summary()
 }
 
-fn (mut context Context) parse_options() ? {
+fn (mut context Context) parse_options() ! {
 	mut fp := flag.new_flag_parser(os.args)
 	fp.application(os.file_name(os.executable()))
 	fp.version('0.0.1')
 	fp.description('Repeat command(s) and collect statistics. Note: you have to quote each command, if it contains spaces.')
 	fp.arguments_description('CMD1 CMD2 ...')
 	fp.skip_executable()
-	fp.limit_free_args_to_at_least(1)?
+	fp.limit_free_args_to_at_least(1)!
 	context.count = fp.int('count', `c`, 10, 'Repetition count.')
 	context.series = fp.int('series', `s`, 2, 'Series count. `-s 2 -c 4 a b` => aaaabbbbaaaabbbb, while `-s 3 -c 2 a b` => aabbaabbaabb.')
 	context.warmup = fp.int('warmup', `w`, 2, 'Warmup runs. These are done *only at the start*, and are ignored.')

cmd/tools/test_if_v_test_system_works.v

@@ -60,16 +60,16 @@ fn (result MyResult) matches(gpattern string) MyResult {
 	return result
 }
 
-fn create_test(tname string, tcontent string) ?string {
+fn create_test(tname string, tcontent string) !string {
 	tpath := os.join_path(tdir, tname)
-	os.write_file(tpath, tcontent)?
+	os.write_file(tpath, tcontent)!
 	eprintln('>>>>>>>> tpath: $tpath | tcontent: $tcontent')
 	return os.quoted_path(tpath)
 }
 
-fn check_assert_continues_works() ? {
-	os.chdir(tdir)?
-	create_test('assert_continues_option_works_test.v', 'fn test_fail1() { assert 2==4\nassert 2==1\nassert 2==0 }\nfn test_ok(){ assert true }\nfn test_fail2() { assert false }')?
+fn check_assert_continues_works() ! {
+	os.chdir(tdir)!
+	create_test('assert_continues_option_works_test.v', 'fn test_fail1() { assert 2==4\nassert 2==1\nassert 2==0 }\nfn test_ok(){ assert true }\nfn test_fail2() { assert false }')!
 	result := check_fail('$vexe -assert continues assert_continues_option_works_test.v')
 	result.has('assert_continues_option_works_test.v:1: fn test_fail1')
 	result.has('assert_continues_option_works_test.v:2: fn test_fail1')
@@ -77,7 +77,7 @@ fn check_assert_continues_works() ? {
 	result.has('assert_continues_option_works_test.v:5: fn test_fail2')
 	result.has('> assert 2 == 4').has('> assert 2 == 1').has('> assert 2 == 0')
 	// Check if a test function, tagged with [assert_continues], has the same behaviour, without needing additional options
-	create_test('assert_continues_tag_works_test.v', '[assert_continues]fn test_fail1() { assert 2==4\nassert 2==1\nassert 2==0 }\nfn test_ok(){ assert true }\nfn test_fail2() { assert false\n assert false }')?
+	create_test('assert_continues_tag_works_test.v', '[assert_continues]fn test_fail1() { assert 2==4\nassert 2==1\nassert 2==0 }\nfn test_ok(){ assert true }\nfn test_fail2() { assert false\n assert false }')!
 	tag_res := check_fail('$vexe assert_continues_tag_works_test.v')
 	tag_res.has('assert_continues_tag_works_test.v:1: fn test_fail1')
 	tag_res.has('assert_continues_tag_works_test.v:2: fn test_fail1')
@@ -113,23 +113,23 @@ fn main() {
 		os.chdir(os.wd_at_startup) or {}
 	}
 	println('> vroot: $vroot | vexe: $vexe | tdir: $tdir')
-	ok_fpath := create_test('a_single_ok_test.v', 'fn test_ok(){ assert true }')?
+	ok_fpath := create_test('a_single_ok_test.v', 'fn test_ok(){ assert true }')!
 	if check_ok('$vexe $ok_fpath') != '' {
 		exit(1)
 	}
 	check_ok('$vexe test $ok_fpath').matches('*OK*a_single_ok_test.v*')
 	check_ok('$vexe test "$tdir"').matches('*OK*a_single_ok_test.v*')
 	//
-	fail_fpath := create_test('a_single_failing_test.v', 'fn test_fail(){ assert 1 == 2 }')?
+	fail_fpath := create_test('a_single_failing_test.v', 'fn test_fail(){ assert 1 == 2 }')!
 	check_fail('$vexe $fail_fpath').has('> assert 1 == 2').has('a_single_failing_test.v:1: fn test_fail')
 	check_fail('$vexe test $fail_fpath').has('> assert 1 == 2').has('a_single_failing_test.v:1: fn test_fail')
 	check_fail('$vexe test "$tdir"').has('> assert 1 == 2')
 	rel_dir := os.join_path(tdir, rand.ulid())
-	os.mkdir(rel_dir)?
-	os.chdir(rel_dir)?
+	os.mkdir(rel_dir)!
+	os.chdir(rel_dir)!
 	relative_path := '..' + os.path_separator + 'a_single_ok_test.v'
 	check_ok('$vexe test ${os.quoted_path(relative_path)}').has('OK').has('a_single_ok_test.v')
 	//
-	check_assert_continues_works()?
+	check_assert_continues_works()!
 	println('> all done')
 }

cmd/tools/translate.v

@@ -16,9 +16,9 @@ fn main() {
 	}
 	// Git clone c2v
 	if !os.exists(c2v_dir) {
-		os.mkdir_all(vmodules)?
+		os.mkdir_all(vmodules)!
 		println('C2V is not installed. Cloning C2V to $c2v_dir ...')
-		os.chdir(vmodules)?
+		os.chdir(vmodules)!
 		res := os.execute('git clone https://github.com/vlang/c2v')
 		if res.exit_code != 0 {
 			eprintln('Failed to download C2V.')
@@ -27,7 +27,7 @@ fn main() {
 	}
 	// Compile c2v
 	if !os.exists(c2v_bin) {
-		os.chdir(c2v_dir)?
+		os.chdir(c2v_dir)!
 		println('Compiling c2v ...')
 		res2 := os.execute('${os.quoted_path(vexe)} -o ${os.quoted_path(c2v_bin)} -keepc -g -experimental .')
 		if res2.exit_code != 0 {
@@ -42,7 +42,7 @@ fn main() {
 	}
 	passed_args := util.args_quote_paths(os.args[2..])
 	// println(passed_args)
-	os.chdir(os.wd_at_startup)?
+	os.chdir(os.wd_at_startup)!
 	c2v_cmd := '${os.quoted_path(c2v_bin)} $passed_args'
 	res := os.system(c2v_cmd)
 	if res != 0 {

cmd/tools/vast/vast.v

@@ -44,7 +44,7 @@ fn main() {
 	for hf in hfields.split(',') {
 		ctx.hide_names[hf] = true
 	}
-	fp.limit_free_args_to_at_least(1)?
+	fp.limit_free_args_to_at_least(1)!
 	rest_of_args := fp.remaining_parameters()
 	for vfile in rest_of_args {
 		file := get_abs_path(vfile)

cmd/tools/vbin2v.v

@@ -73,7 +73,7 @@ fn (context Context) file2v(bname string, fbytes []u8, bn_max int) string {
 	return sb.str()
 }
 
-fn (context Context) bname_and_bytes(file string) ?(string, []u8) {
+fn (context Context) bname_and_bytes(file string) !(string, []u8) {
 	fname := os.file_name(file)
 	fname_escaped := fname.replace_each(['.', '_', '-', '_'])
 	byte_name := '$context.prefix$fname_escaped'.to_lower()
@@ -130,12 +130,12 @@ fn main() {
 	}
 	max_bname := context.max_bname_len(file_byte_map.keys())
 	if context.write_file.len > 0 {
-		mut out_file := os.create(context.write_file)?
-		out_file.write_string(context.header())?
+		mut out_file := os.create(context.write_file)!
+		out_file.write_string(context.header())!
 		for bname, fbytes in file_byte_map {
-			out_file.write_string(context.file2v(bname, fbytes, max_bname))?
+			out_file.write_string(context.file2v(bname, fbytes, max_bname))!
 		}
-		out_file.write_string(context.footer())?
+		out_file.write_string(context.footer())!
 	} else {
 		print(context.header())
 		for bname, fbytes in file_byte_map {

cmd/tools/vbuild-tools.v

@@ -23,7 +23,7 @@ fn main() {
 	args_string := os.args[1..].join(' ')
 	vexe := os.getenv('VEXE')
 	vroot := os.dir(vexe)
-	os.chdir(vroot)?
+	os.chdir(vroot)!
 	folder := os.join_path('cmd', 'tools')
 	tfolder := os.join_path(vroot, 'cmd', 'tools')
 	main_label := 'Building $folder ...'
@@ -47,7 +47,7 @@ fn main() {
 		exit(1)
 	}
 	//
-	mut executables := os.ls(session.vtmp_dir)?
+	mut executables := os.ls(session.vtmp_dir)!
 	executables.sort()
 	for texe in executables {
 		tname := texe.replace(os.file_ext(texe), '')

cmd/tools/vbump_test.v

@@ -73,25 +73,25 @@ fn main() {
 	},
 ]
 
-fn run_individual_test(case BumpTestCase) ? {
+fn run_individual_test(case BumpTestCase) ! {
 	test_file := os.join_path_single(tfolder, case.file_name)
 
 	os.rm(test_file) or {}
-	os.write_file(test_file, case.contents)?
+	os.write_file(test_file, case.contents)!
 	//
 	os.execute_or_exit('${os.quoted_path(vexe)} bump --patch ${os.quoted_path(test_file)}')
-	patch_lines := os.read_lines(test_file)?
+	patch_lines := os.read_lines(test_file)!
 	assert patch_lines[case.line] == case.expected_patch
 
 	os.execute_or_exit('${os.quoted_path(vexe)} bump --minor ${os.quoted_path(test_file)}')
-	minor_lines := os.read_lines(test_file)?
+	minor_lines := os.read_lines(test_file)!
 	assert minor_lines[case.line] == case.expected_minor
 
 	os.execute_or_exit('${os.quoted_path(vexe)} bump --major ${os.quoted_path(test_file)}')
-	major_lines := os.read_lines(test_file)?
+	major_lines := os.read_lines(test_file)!
 	assert major_lines[case.line] == case.expected_major
 	//
-	os.rm(test_file)?
+	os.rm(test_file)!
 }
 
 fn test_all_bump_cases() {

cmd/tools/vcreate_test.v

@@ -2,10 +2,10 @@ import os
 
 const test_path = os.join_path(os.temp_dir(), 'v', 'vcreate_test')
 
-fn init_and_check() ? {
+fn init_and_check() ! {
 	os.execute_or_exit('${os.quoted_path(@VEXE)} init')
 
-	assert os.read_file('vcreate_test.v')? == [
+	assert os.read_file('vcreate_test.v')! == [
 		'module main\n',
 		'fn main() {',
 		"	println('Hello World!')",
@@ -13,7 +13,7 @@ fn init_and_check() ? {
 		'',
 	].join_lines()
 
-	assert os.read_file('v.mod')? == [
+	assert os.read_file('v.mod')! == [
 		'Module {',
 		"	name: 'vcreate_test'",
 		"	description: ''",
@@ -24,7 +24,7 @@ fn init_and_check() ? {
 		'',
 	].join_lines()
 
-	assert os.read_file('.gitignore')? == [
+	assert os.read_file('.gitignore')! == [
 		'# Binaries for programs and plugins',
 		'main',
 		'vcreate_test',
@@ -37,7 +37,7 @@ fn init_and_check() ? {
 		'',
 	].join_lines()
 
-	assert os.read_file('.gitattributes')? == [
+	assert os.read_file('.gitattributes')! == [
 		'*.v linguist-language=V text=auto eol=lf',
 		'*.vv linguist-language=V text=auto eol=lf',
 		'*.vsh linguist-language=V text=auto eol=lf',
@@ -45,7 +45,7 @@ fn init_and_check() ? {
 		'',
 	].join_lines()
 
-	assert os.read_file('.editorconfig')? == [
+	assert os.read_file('.editorconfig')! == [
 		'[*]',
 		'charset = utf-8',
 		'end_of_line = lf',
@@ -59,28 +59,28 @@ fn init_and_check() ? {
 	].join_lines()
 }
 
-fn prepare_test_path() ? {
+fn prepare_test_path() ! {
 	os.rmdir_all(test_path) or {}
 	os.mkdir_all(test_path) or {}
-	os.chdir(test_path)?
+	os.chdir(test_path)!
 }
 
 fn test_v_init() {
-	prepare_test_path()?
-	init_and_check()?
+	prepare_test_path()!
+	init_and_check()!
 }
 
 fn test_v_init_in_git_dir() {
-	prepare_test_path()?
+	prepare_test_path()!
 	os.execute_or_exit('git init .')
-	init_and_check()?
+	init_and_check()!
 }
 
 fn test_v_init_no_overwrite_gitignore() {
-	prepare_test_path()?
-	os.write_file('.gitignore', 'blah')?
+	prepare_test_path()!
+	os.write_file('.gitignore', 'blah')!
 	os.execute_or_exit('${os.quoted_path(@VEXE)} init')
-	assert os.read_file('.gitignore')? == 'blah'
+	assert os.read_file('.gitignore')! == 'blah'
 }
 
 fn test_v_init_no_overwrite_gitattributes_and_editorconfig() {
@@ -95,13 +95,13 @@ trim_trailing_whitespace = true
 indent_style = tab
 indent_size = 4
 '
-	prepare_test_path()?
-	os.write_file('.gitattributes', git_attributes_content)?
-	os.write_file('.editorconfig', editor_config_content)?
+	prepare_test_path()!
+	os.write_file('.gitattributes', git_attributes_content)!
+	os.write_file('.editorconfig', editor_config_content)!
 	os.execute_or_exit('${os.quoted_path(@VEXE)} init')
 
-	assert os.read_file('.gitattributes')? == git_attributes_content
-	assert os.read_file('.editorconfig')? == editor_config_content
+	assert os.read_file('.gitattributes')! == git_attributes_content
+	assert os.read_file('.editorconfig')! == editor_config_content
 }
 
 fn testsuite_end() {

cmd/tools/vgret.v

@@ -166,7 +166,7 @@ fn main() {
 	}
 
 	toml_conf := fp.string('toml-config', `t`, default_toml, 'Path or string with TOML configuration')
-	arg_paths := fp.finalize()?
+	arg_paths := fp.finalize()!
 	if show_help {
 		println(fp.usage())
 		exit(0)
@@ -179,7 +179,7 @@ fn main() {
 	}
 
 	if !os.exists(tmp_dir) {
-		os.mkdir_all(tmp_dir)?
+		os.mkdir_all(tmp_dir)!
 	}
 
 	opt.config = new_config(opt.root_path, toml_conf) or { panic(err) }
@@ -202,7 +202,7 @@ fn main() {
 			eprintln('Compare paths can not be the same directory `$path`/`$target_path`/`$gen_in_path`')
 			exit(1)
 		}
-		compare_screenshots(opt, gen_in_path, target_path)?
+		compare_screenshots(opt, gen_in_path, target_path)!
 	}
 }
 
@@ -254,7 +254,7 @@ fn generate_screenshots(mut opt Options, output_path string) ! {
 	}
 }
 
-fn compare_screenshots(opt Options, output_path string, target_path string) ? {
+fn compare_screenshots(opt Options, output_path string, target_path string) ! {
 	mut fails := map[string]string{}
 	mut warns := map[string]string{}
 	for app_config in opt.config.apps {
@@ -306,14 +306,14 @@ fn compare_screenshots(opt Options, output_path string, target_path string) ? {
 		}
 		first := fails.keys()[0]
 		fail_copy := os.join_path(os.temp_dir(), 'fail.' + first.all_after_last('.'))
-		os.cp(first, fail_copy)?
+		os.cp(first, fail_copy)!
 		eprintln('First failed file `$first` is copied to `$fail_copy`')
 
 		diff_file := os.join_path(os.temp_dir(), os.file_name(first).all_before_last('.') +
 			'.diff.tif')
 		diff_copy := os.join_path(os.temp_dir(), 'diff.tif')
 		if os.is_file(diff_file) {
-			os.cp(diff_file, diff_copy)?
+			os.cp(diff_file, diff_copy)!
 			eprintln('First failed diff file `$diff_file` is copied to `$diff_copy`')
 			eprintln('Removing alpha channel from $diff_copy ...')
 			final_fail_result_file := os.join_path(os.temp_dir(), 'diff.png')

cmd/tools/vls.v

@@ -67,16 +67,16 @@ const json_enc = json2.Encoder{
 	escape_unicode: false
 }
 
-fn (upd VlsUpdater) check_or_create_vls_folder() ? {
+fn (upd VlsUpdater) check_or_create_vls_folder() ! {
 	if !os.exists(vls_folder) {
 		upd.log('Creating .vls folder...')
-		os.mkdir(vls_folder)?
+		os.mkdir(vls_folder)!
 	}
 }
 
-fn (upd VlsUpdater) manifest_config() ?map[string]json2.Any {
+fn (upd VlsUpdater) manifest_config() !map[string]json2.Any {
 	manifest_buf := os.read_file(vls_manifest_path) or { '{}' }
-	manifest_contents := json2.raw_decode(manifest_buf)?.as_map()
+	manifest_contents := json2.raw_decode(manifest_buf)!.as_map()
 	return manifest_contents
 }
 
@@ -88,9 +88,9 @@ fn (upd VlsUpdater) exec_asset_file_name() string {
 	return 'vls_${os_name}_${arch + ext}'
 }
 
-fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp time.Time) ? {
+fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp time.Time) ! {
 	upd.log('Updating permissions...')
-	os.chmod(new_path, 755)?
+	os.chmod(new_path, 755)!
 
 	upd.log('Updating vls.config.json...')
 	mut manifest := upd.manifest_config() or {
@@ -103,7 +103,7 @@ fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp
 		}
 	}
 
-	mut manifest_file := os.open_file(vls_manifest_path, 'w+')?
+	mut manifest_file := os.open_file(vls_manifest_path, 'w+')!
 	defer {
 		manifest_file.close()
 	}
@@ -112,31 +112,31 @@ fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp
 	manifest['last_updated'] = json2.Any(timestamp.format_ss())
 	manifest['from_source'] = json2.Any(from_source)
 
-	json_enc.encode_value(manifest, mut manifest_file)?
+	json_enc.encode_value(manifest, mut manifest_file)!
 }
 
-fn (upd VlsUpdater) init_download_prebuilt() ? {
+fn (upd VlsUpdater) init_download_prebuilt() ! {
 	if !os.exists(vls_cache_folder) {
-		os.mkdir(vls_cache_folder)?
+		os.mkdir(vls_cache_folder)!
 	}
 
 	if os.exists(vls_bin_folder) {
-		os.rmdir_all(vls_bin_folder)?
+		os.rmdir_all(vls_bin_folder)!
 	}
 
-	os.mkdir(vls_bin_folder)?
+	os.mkdir(vls_bin_folder)!
 }
 
-fn (upd VlsUpdater) get_last_updated_at() ?time.Time {
+fn (upd VlsUpdater) get_last_updated_at() !time.Time {
 	if manifest := upd.manifest_config() {
 		if 'last_updated' in manifest {
-			return time.parse(manifest['last_updated'] or { '' }.str()) or { return none }
+			return time.parse(manifest['last_updated'] or { '' }.str()) or { return error('none') }
 		}
 	}
-	return none
+	return error('none')
 }
 
-fn (upd VlsUpdater) download_prebuilt() ? {
+fn (upd VlsUpdater) download_prebuilt() ! {
 	mut has_last_updated_at := true
 	last_updated_at := upd.get_last_updated_at() or {
 		has_last_updated_at = false
@@ -147,14 +147,15 @@ fn (upd VlsUpdater) download_prebuilt() ? {
 	}
 
 	upd.log('Finding prebuilt executables from GitHub release..')
-	resp := http.get('https://api.github.com/repos/vlang/vls/releases')?
-	releases_json := json2.raw_decode(resp.body)?.arr()
+	resp := http.get('https://api.github.com/repos/vlang/vls/releases')!
+	releases_json := json2.raw_decode(resp.body)!.arr()
 	if releases_json.len == 0 {
 		return error('Unable to fetch latest VLS release data: No releases found.')
 	}
 
 	latest_release := releases_json[0].as_map()
-	assets := latest_release['assets']?.arr()
+	latest_assets := latest_release['assets'] or { return }
+	assets := latest_assets.arr()
 
 	mut checksum_asset_idx := -1
 	mut exec_asset_idx := -1
@@ -164,7 +165,8 @@ fn (upd VlsUpdater) download_prebuilt() ? {
 
 	for asset_idx, raw_asset in assets {
 		asset := raw_asset.as_map()
-		match asset['name']?.str() {
+		t_asset := asset['name'] or { return }
+		match t_asset.str() {
 			exp_asset_name {
 				exec_asset_idx = asset_idx
 
@@ -196,13 +198,15 @@ fn (upd VlsUpdater) download_prebuilt() ? {
 	}
 
 	upd.log('Executable found for this system. Downloading...')
-	upd.init_download_prebuilt()?
-	http.download_file(exec_asset['browser_download_url']?.str(), exec_asset_file_path)?
+	upd.init_download_prebuilt()!
+	t_asset := exec_asset['browser_download_url'] or { return }
+	http.download_file(t_asset.str(), exec_asset_file_path)!
 
 	checksum_file_path := os.join_path(vls_cache_folder, 'checksums.txt')
 	checksum_file_asset := assets[checksum_asset_idx].as_map()
-	http.download_file(checksum_file_asset['browser_download_url']?.str(), checksum_file_path)?
-	checksums := os.read_file(checksum_file_path)?.split_into_lines()
+	t_checksum_asset := checksum_file_asset['browser_download_url'] or { return }
+	http.download_file(t_checksum_asset.str(), checksum_file_path)!
+	checksums := os.read_file(checksum_file_path)!.split_into_lines()
 
 	upd.log('Verifying checksum...')
 	for checksum_result in checksums {
@@ -217,7 +221,7 @@ fn (upd VlsUpdater) download_prebuilt() ? {
 	}
 
 	new_exec_path := os.join_path(vls_bin_folder, exp_asset_name)
-	os.cp(exec_asset_file_path, new_exec_path)?
+	os.cp(exec_asset_file_path, new_exec_path)!
 	upd.update_manifest(new_exec_path, false, asset_last_updated_at) or {
 		upd.log('Unable to update config but the executable was updated successfully.')
 	}
@@ -231,12 +235,12 @@ fn (upd VlsUpdater) print_new_vls_version(new_vls_exec_path string) {
 	}
 }
 
-fn calculate_checksum(file_path string) ?string {
-	data := os.read_file(file_path)?
+fn calculate_checksum(file_path string) !string {
+	data := os.read_file(file_path)!
 	return sha256.hexhash(data)
 }
 
-fn (upd VlsUpdater) compile_from_source() ? {
+fn (upd VlsUpdater) compile_from_source() ! {
 	git := os.find_abs_path_of_executable('git') or { return error('Git not found.') }
 
 	if !os.exists(vls_src_folder) {
@@ -280,22 +284,22 @@ fn (upd VlsUpdater) compile_from_source() ? {
 	upd.print_new_vls_version(exec_path)
 }
 
-fn (upd VlsUpdater) find_ls_path() ?string {
-	manifest := upd.manifest_config()?
+fn (upd VlsUpdater) find_ls_path() !string {
+	manifest := upd.manifest_config()!
 	if 'server_path' in manifest {
-		server_path := manifest['server_path']?
+		server_path := manifest['server_path'] or { return error('none') }
 		if server_path is string {
 			if server_path.len == 0 {
-				return none
+				return error('none')
 			}
 
 			return server_path
 		}
 	}
-	return none
+	return error('none')
 }
 
-fn (mut upd VlsUpdater) parse(mut fp flag.FlagParser) ? {
+fn (mut upd VlsUpdater) parse(mut fp flag.FlagParser) ! {
 	is_json := fp.bool('json', ` `, false, 'Print the output as JSON.')
 	if is_json {
 		upd.output = .json
@@ -364,7 +368,7 @@ fn (mut upd VlsUpdater) parse(mut fp flag.FlagParser) ? {
 		fp.allow_unknown_args()
 		upd.args << fp.finalize() or { fp.remaining_parameters() }
 	} else {
-		fp.finalize()?
+		fp.finalize()!
 	}
 }
 
@@ -436,23 +440,23 @@ fn (upd VlsUpdater) check_installation() {
 	}
 }
 
-fn (upd VlsUpdater) run(fp flag.FlagParser) ? {
+fn (upd VlsUpdater) run(fp flag.FlagParser) ! {
 	if upd.is_check {
 		upd.check_installation()
 	} else if upd.setup_kind != .none_ {
-		upd.check_or_create_vls_folder()?
+		upd.check_or_create_vls_folder()!
 
 		match upd.update_source {
 			.github_releases {
 				upd.download_prebuilt() or {
 					if err.code() == 100 {
-						upd.compile_from_source()?
+						upd.compile_from_source()!
 					}
 					return err
 				}
 			}
 			.git_repo {
-				upd.compile_from_source()?
+				upd.compile_from_source()!
 			}
 		}
 	} else if upd.pass_to_ls {

cmd/tools/vrepl.v

@@ -133,7 +133,7 @@ fn (r &Repl) function_call(line string) (bool, FnType) {
 // TODO(vincenzopalazzo) Remove this fancy check and add a regex
 fn (r &Repl) is_function_call(line string) bool {
 	return !line.starts_with('[') && line.contains('.') && line.contains('(')
-		&& (line.ends_with(')') || line.ends_with('?'))
+		&& (line.ends_with(')') || line.ends_with('?') || line.ends_with('!'))
 }
 
 // Convert the list of modules that we parsed already,

cmd/tools/vscan.v

@@ -12,11 +12,11 @@ fn main() {
 	fp.version('0.0.1')
 	fp.description('\nScan .v source files, and print the V tokens contained in them.')
 	fp.arguments_description('PATH [PATH]...')
-	fp.limit_free_args_to_at_least(1)?
+	fp.limit_free_args_to_at_least(1)!
 	pref := pref.new_preferences()
 	mut all_paths := fp.remaining_parameters()
 	for path in all_paths {
-		mut scanner := scanner.new_scanner_file(path, .parse_comments, pref)?
+		mut scanner := scanner.new_scanner_file(path, .parse_comments, pref)!
 		mut tok := token.Token{}
 		for tok.kind != .eof {
 			tok = scanner.scan()

cmd/tools/vself.v

@@ -15,7 +15,7 @@ fn main() {
 	short_v_name := vexe_name.all_before('.')
 	//
 	recompilation.must_be_enabled(vroot, 'Please install V from source, to use `$vexe_name self` .')
-	os.chdir(vroot)?
+	os.chdir(vroot)!
 	os.setenv('VCOLORS', 'always', true)
 	args := os.args[1..].filter(it != 'self')
 	jargs := args.join(' ')
@@ -60,7 +60,7 @@ fn list_folder(short_v_name string, bmessage string, message string) {
 	println(message)
 }
 
-fn backup_old_version_and_rename_newer(short_v_name string) ?bool {
+fn backup_old_version_and_rename_newer(short_v_name string) !bool {
 	mut errors := []string{}
 	short_v_file := if os.user_os() == 'windows' { '${short_v_name}.exe' } else { '$short_v_name' }
 	short_v2_file := if os.user_os() == 'windows' { 'v2.exe' } else { 'v2' }

cmd/tools/vsetup-freetype.v

@@ -11,7 +11,7 @@ fn main() {
 	$if windows {
 		println('Setup freetype...')
 		vroot := os.dir(pref.vexe_path())
-		os.chdir(vroot)?
+		os.chdir(vroot)!
 		if os.is_dir(freetype_folder) {
 			println('Thirdparty "freetype" is already installed.')
 		} else {

cmd/tools/vshader.v

@@ -122,7 +122,7 @@ fn shader_program_name(shader_file string) string {
 }
 
 // validate_shader_file returns an error if `shader_file` isn't valid.
-fn validate_shader_file(shader_file string) ? {
+fn validate_shader_file(shader_file string) ! {
 	shader_program := os.read_lines(shader_file) or {
 		return error('shader program at "$shader_file" could not be opened for reading')
 	}
@@ -140,7 +140,7 @@ fn validate_shader_file(shader_file string) ? {
 
 // compile_shaders compiles all `*.glsl` files found in `input_path`
 // to their C header file representatives.
-fn compile_shaders(opt Options, input_path string) ? {
+fn compile_shaders(opt Options, input_path string) ! {
 	mut path := os.real_path(input_path)
 	path = path.trim_right('/')
 	if os.is_file(path) {
@@ -172,12 +172,12 @@ fn compile_shaders(opt Options, input_path string) ? {
 		// Currently sokol-shdc allows for multiple --input flags
 		// - but it's only the last entry that's actually compiled/used
 		// Given this fact - we can only compile one '.glsl' file to one C '.h' header
-		compile_shader(co, shader_file)?
+		compile_shader(co, shader_file)!
 	}
 }
 
 // compile_shader compiles `shader_file` to a C header file.
-fn compile_shader(opt CompileOptions, shader_file string) ? {
+fn compile_shader(opt CompileOptions, shader_file string) ! {
 	path := opt.invoke_path
 	// The output convetion, for now, is to use the name of the .glsl file
 	mut out_file := os.file_name(shader_file).all_before_last('.') + '.h'
@@ -231,12 +231,12 @@ fn collect(path string, mut list []string) {
 
 // ensure_external_tools returns nothing if the external
 // tools can be setup or is already in place.
-fn ensure_external_tools(opt Options) ? {
+fn ensure_external_tools(opt Options) ! {
 	if !os.exists(cache_dir) {
-		os.mkdir_all(cache_dir)?
+		os.mkdir_all(cache_dir)!
 	}
 	if opt.force_update {
-		download_shdc(opt)?
+		download_shdc(opt)!
 		return
 	}
 
@@ -250,7 +250,7 @@ fn ensure_external_tools(opt Options) ? {
 		return
 	}
 
-	download_shdc(opt)?
+	download_shdc(opt)!
 }
 
 // shdc_exe returns an absolute path to the `sokol-shdc` tool.
@@ -261,7 +261,7 @@ fn shdc_exe() string {
 }
 
 // download_shdc downloads the `sokol-shdc` tool to an OS specific cache directory.
-fn download_shdc(opt Options) ? {
+fn download_shdc(opt Options) ! {
 	// We want to use the same, runtime, OS type as this tool is invoked on.
 	download_url := shdc_urls[runtime_os] or { '' }
 	if download_url == '' {
@@ -277,26 +277,26 @@ fn download_shdc(opt Options) ? {
 		}
 	}
 	if os.exists(file) {
-		os.rm(file)?
+		os.rm(file)!
 	}
 
-	mut dtmp_file, dtmp_path := util.temp_file(util.TempFileOptions{ path: os.dir(file) })?
+	mut dtmp_file, dtmp_path := util.temp_file(util.TempFileOptions{ path: os.dir(file) })!
 	dtmp_file.close()
 	if opt.verbose {
 		eprintln('$tool_name downloading sokol-shdc from $download_url')
 	}
 	http.download_file(download_url, dtmp_path) or {
-		os.rm(dtmp_path)?
+		os.rm(dtmp_path)!
 		return error('$tool_name failed to download sokol-shdc needed for shader compiling: $err')
 	}
 	// Make it executable
-	os.chmod(dtmp_path, 0o775)?
+	os.chmod(dtmp_path, 0o775)!
 	// Move downloaded file in place
-	os.mv(dtmp_path, file)?
+	os.mv(dtmp_path, file)!
 	if runtime_os in ['linux', 'macos'] {
 		// Use the .exe file ending to minimize platform friction.
-		os.mv(file, shdc)?
+		os.mv(file, shdc)!
 	}
 	// Update internal version file
-	os.write_file(shdc_version_file, update_to_shdc_version)?
+	os.write_file(shdc_version_file, update_to_shdc_version)!
 }

cmd/tools/vtest-parser.v

@@ -54,7 +54,7 @@ fn main() {
 		context.pref = &pref.Preferences{
 			output_mode: .silent
 		}
-		mut source := os.read_file(context.path)?
+		mut source := os.read_file(context.path)!
 		source = source[..context.cut_index]
 
 		go fn (ms int) {

cmd/tools/vtracev.v

@@ -6,7 +6,7 @@ import v.pref
 fn main() {
 	vexe := pref.vexe_path()
 	vroot := os.dir(vexe)
-	os.chdir(vroot)?
+	os.chdir(vroot)!
 	os.setenv('VCOLORS', 'always', true)
 	self_idx := os.args.index('tracev')
 	args := os.args[1..self_idx]

cmd/tools/vup.v

@@ -26,7 +26,7 @@ fn new_app() App {
 fn main() {
 	app := new_app()
 	recompilation.must_be_enabled(app.vroot, 'Please install V from source, to use `v up` .')
-	os.chdir(app.vroot)?
+	os.chdir(app.vroot)!
 	println('Updating V...')
 	app.update_from_master()
 	v_hash := version.githash(false)

cmd/tools/vvet/vet_test.v

@@ -14,7 +14,7 @@ fn find_diff_cmd() string {
 fn test_vet() {
 	vexe := os.getenv('VEXE')
 	vroot := os.dir(vexe)
-	os.chdir(vroot)?
+	os.chdir(vroot)!
 	test_dir := 'cmd/tools/vvet/tests'
 	tests := get_tests_in_dir(test_dir)
 	fails := check_path(vexe, test_dir, tests)

cmd/tools/vwatch.v

@@ -318,7 +318,7 @@ fn main() {
 	fp.description('Collect all .v files needed for a compilation, then re-run the compilation when any of the source changes.')
 	fp.arguments_description('[--silent] [--clear] [--ignore .db] [--add /path/to/a/file.v] [run] program.v')
 	fp.allow_unknown_args()
-	fp.limit_free_args_to_at_least(1)?
+	fp.limit_free_args_to_at_least(1)!
 	context.is_worker = fp.bool('vwatchworker', 0, false, 'Internal flag. Used to distinguish vwatch manager and worker processes.')
 	context.silent = fp.bool('silent', `s`, false, 'Be more silent; do not print the watch timestamp before each re-run.')
 	context.clear_terminal = fp.bool('clear', `c`, false, 'Clears the terminal before each re-run.')

cmd/tools/vwhere/finder_utils.v

@@ -145,7 +145,7 @@ fn maybe_color(term_color fn (string) string, str string) string {
 	}
 }
 
-fn collect_v_files(path string, recursive bool) ?[]string {
+fn collect_v_files(path string, recursive bool) ![]string {
 	if path.len == 0 {
 		return error('path cannot be empty')
 	}
@@ -153,7 +153,7 @@ fn collect_v_files(path string, recursive bool) ?[]string {
 		return error('path does not exist or is not a directory')
 	}
 	mut all_files := []string{}
-	mut entries := os.ls(path)?
+	mut entries := os.ls(path)!
 	mut local_path_separator := os.path_separator
 	if path.ends_with(os.path_separator) {
 		local_path_separator = ''
@@ -161,7 +161,7 @@ fn collect_v_files(path string, recursive bool) ?[]string {
 	for entry in entries {
 		file := path + local_path_separator + entry
 		if os.is_dir(file) && !os.is_link(file) && recursive {
-			all_files << collect_v_files(file, recursive)?
+			all_files << collect_v_files(file, recursive)!
 		} else if os.exists(file) && (file.ends_with('.v') || file.ends_with('.vsh')) {
 			all_files << file
 		}
@@ -169,7 +169,7 @@ fn collect_v_files(path string, recursive bool) ?[]string {
 	return all_files
 }
 
-fn resolve_module(path string) ?string {
+fn resolve_module(path string) !string {
 	if os.is_dir(path) {
 		return path
 	} else if os.is_dir(os.join_path(vmod_dir, path)) {

doc/docs.md

@@ -1901,8 +1901,8 @@ enum State {
 }
 
 // write log file and return number of bytes written
-fn write_log(s State) ?int {
-	mut f := os.create('log.txt')?
+fn write_log(s State) !int {
+	mut f := os.create('log.txt')!
 	defer {
 		f.close()
 	}

examples/buf_reader.v

@@ -5,9 +5,9 @@ import io
 
 fn main() {
 	// Make a new connection
-	mut conn := net.dial_tcp('google.com:80')?
+	mut conn := net.dial_tcp('google.com:80')!
 	// Simple http HEAD request for a file
-	conn.write_string('GET /index.html HTTP/1.0\r\n\r\n')?
+	conn.write_string('GET /index.html HTTP/1.0\r\n\r\n')!
 	// Wrap in a buffered reader
 	mut r := io.new_buffered_reader(reader: conn)
 	for {

examples/concurrency/concurrency_http.v

@@ -2,9 +2,9 @@ import net.http
 import sync
 import time
 
-fn vlang_time(mut wg sync.WaitGroup) ?string {
+fn vlang_time(mut wg sync.WaitGroup) !string {
 	start := time.ticks()
-	data := http.get('https://vlang.io/utc_now')?
+	data := http.get('https://vlang.io/utc_now')!
 	finish := time.ticks()
 	println('Finish getting time ${finish - start} ms')
 	println(data.body)
@@ -12,9 +12,9 @@ fn vlang_time(mut wg sync.WaitGroup) ?string {
 	return data.body
 }
 
-fn remote_ip(mut wg sync.WaitGroup) ?string {
+fn remote_ip(mut wg sync.WaitGroup) !string {
 	start := time.ticks()
-	data := http.get('https://api.ipify.org')?
+	data := http.get('https://api.ipify.org')!
 	finish := time.ticks()
 	println('Finish getting ip ${finish - start} ms')
 	println(data.body)

examples/dynamic_library_loading/use.v

@@ -10,9 +10,9 @@ type FNAdder = fn (int, int) int
 
 fn main() {
 	library_file_path := os.join_path(os.dir(@FILE), dl.get_libname('library'))
-	handle := dl.open_opt(library_file_path, dl.rtld_lazy)?
+	handle := dl.open_opt(library_file_path, dl.rtld_lazy)!
 	eprintln('handle: ${ptr_str(handle)}')
-	f := FNAdder(dl.sym_opt(handle, 'add_1')?)
+	f := FNAdder(dl.sym_opt(handle, 'add_1')!)
 	eprintln('f: ${ptr_str(f)}')
 	res := f(1, 2)
 	eprintln('res: $res')

examples/http_server.v

@@ -34,5 +34,5 @@ fn main() {
 	mut server := Server{
 		handler: ExampleHandler{}
 	}
-	server.listen_and_serve()?
+	server.listen_and_serve()
 }

examples/mini_calculator.v

@@ -5,7 +5,7 @@ import os
 const numeric_char = [`0`, `1`, `2`, `3`, `4`, `5`, `6`, `7`, `8`, `9`, `.`, `e`, `E`]
 
 // Convert expression to Reverse Polish Notation.
-fn expr_to_rev_pol(expr string) ?[]string {
+fn expr_to_rev_pol(expr string) ![]string {
 	if expr == '' {
 		return error('err: empty expression')
 	}
@@ -63,7 +63,7 @@ fn expr_to_rev_pol(expr string) ?[]string {
 }
 
 // Evaluate the result of Reverse Polish Notation.
-fn eval_rev_pol(rev_pol []string) ?f64 {
+fn eval_rev_pol(rev_pol []string) !f64 {
 	mut stack := []f64{}
 	for item in rev_pol {
 		if is_num_string(item) {

examples/net_failconnect.v

@@ -1,5 +1,5 @@
 import net
 
-conn := net.dial_tcp('[::1]:57000')?
-peer_addr := conn.peer_addr()?
+conn := net.dial_tcp('[::1]:57000')!
+peer_addr := conn.peer_addr()!
 println('$peer_addr')

examples/net_peer_ip.v

@@ -1,5 +1,5 @@
 import net
 
-conn := net.dial_tcp('google.com:80')?
-peer_addr := conn.peer_addr()?
+conn := net.dial_tcp('google.com:80')!
+peer_addr := conn.peer_addr()!
 println('$peer_addr')

examples/net_raw_http.v

@@ -3,18 +3,18 @@ import io
 
 fn main() {
 	// Make a new connection
-	mut conn := net.dial_tcp('google.com:80')?
+	mut conn := net.dial_tcp('google.com:80')!
 	defer {
 		conn.close() or {}
 	}
 
-	println(' peer: ${conn.peer_addr()?}')
-	println('local: ${conn.addr()?}')
+	println(' peer: ${conn.peer_addr()!}')
+	println('local: ${conn.addr()!}')
 
 	// Simple http HEAD request for a file
-	conn.write_string('HEAD /index.html HTTP/1.0\r\n\r\n')?
+	conn.write_string('HEAD /index.html HTTP/1.0\r\n\r\n')!
 	// Read all the data that is waiting
-	result := io.read_all(reader: conn)?
+	result := io.read_all(reader: conn)!
 	// Cast to string and print result
 	println(result.bytestr())
 }

examples/net_t.v

@@ -2,9 +2,9 @@ import net.http
 import sync
 import time
 
-fn send_request(mut wg sync.WaitGroup) ?string {
+fn send_request(mut wg sync.WaitGroup) !string {
 	start := time.ticks()
-	data := http.get('https://google.com')?
+	data := http.get('https://google.com')!
 	finish := time.ticks()
 	println('Finish getting time ${finish - start} ms')
 	wg.done()

examples/net_udp_server_and_client.v

@@ -12,7 +12,7 @@ fn main() {
 	mut buf := []u8{len: 100}
 	if is_server {
 		println('UDP echo server, listening for udp packets on port: $port')
-		mut c := net.listen_udp(':$port')?
+		mut c := net.listen_udp(':$port')!
 		for {
 			read, addr := c.read(mut buf) or { continue }
 			println('received $read bytes from $addr')
@@ -23,7 +23,7 @@ fn main() {
 		}
 	} else {
 		println('UDP client, sending packets to port: ${port}.\nType `exit` to exit.')
-		mut c := net.dial_udp('localhost:$port')?
+		mut c := net.dial_udp('localhost:$port')!
 		for {
 			mut line := os.input('client > ')
 			match line {
@@ -36,8 +36,8 @@ fn main() {
 				}
 				else {}
 			}
-			c.write_string(line)?
-			read, _ := c.read(mut buf)?
+			c.write_string(line)!
+			read, _ := c.read(mut buf)!
 			println('server : ' + buf[0..read].bytestr())
 		}
 	}

examples/pendulum-simulation/animation.v

@@ -6,7 +6,7 @@ import sim.anim
 import sim.args as simargs
 
 fn main() {
-	args := simargs.parse_args(extra_workers: 1)? as simargs.ParallelArgs
+	args := simargs.parse_args(extra_workers: 1)! as simargs.ParallelArgs
 
 	mut app := anim.new_app(args)
 	mut workers := []thread{cap: args.workers}
@@ -27,7 +27,7 @@ fn main() {
 		workers << go sim.sim_worker(id, app.request_chan, [app.result_chan])
 	}
 
-	handle_request := fn [app] (request &sim.SimRequest) ? {
+	handle_request := fn [app] (request &sim.SimRequest) ! {
 		app.request_chan <- request
 	}
 

examples/pendulum-simulation/full.v

@@ -7,11 +7,11 @@ import sim.args as simargs
 import sim.img
 
 fn main() {
-	args := simargs.parse_args(extra_workers: 2)? as simargs.ParallelArgs
+	args := simargs.parse_args(extra_workers: 2)! as simargs.ParallelArgs
 
 	img_settings := img.image_settings_from_grid(args.grid)
 
-	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)?
+	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)!
 
 	mut app := anim.new_app(args)
 	mut workers := []thread{cap: args.workers + 1}
@@ -41,7 +41,7 @@ fn main() {
 		workers << go sim.sim_worker(id, app.request_chan, [app.result_chan, img_result_chan])
 	}
 
-	handle_request := fn [app] (request &sim.SimRequest) ? {
+	handle_request := fn [app] (request &sim.SimRequest) ! {
 		app.request_chan <- request
 	}
 

examples/pendulum-simulation/modules/sim/args/parser.v

@@ -31,21 +31,21 @@ pub:
 
 pub type SimArgs = ParallelArgs | SequentialArgs
 
-pub fn parse_args(config ParserSettings) ?SimArgs {
+pub fn parse_args(config ParserSettings) !SimArgs {
 	if config.sequential {
-		args := parse_sequential_args()?
+		args := parse_sequential_args()!
 		return SimArgs(args)
 	} else {
-		args := parse_parallel_args(config.extra_workers)?
+		args := parse_parallel_args(config.extra_workers)!
 		return SimArgs(args)
 	}
 }
 
-fn parse_sequential_args() ?SequentialArgs {
+fn parse_sequential_args() !SequentialArgs {
 	mut fp := flag.new_flag_parser(os.args)
 	fp.application('vps')
 	fp.version('v0.1.0')
-	fp.limit_free_args(0, 0)?
+	fp.limit_free_args(0, 0)!
 	fp.description('This is a pendulum simulation written in pure V')
 	fp.skip_executable()
 
@@ -64,7 +64,7 @@ fn parse_sequential_args() ?SequentialArgs {
 
 	fp.finalize() or {
 		println(fp.usage())
-		return none
+		return error('none')
 	}
 
 	params := sim.sim_params(
@@ -92,11 +92,11 @@ fn parse_sequential_args() ?SequentialArgs {
 	return args
 }
 
-fn parse_parallel_args(extra_workers int) ?ParallelArgs {
+fn parse_parallel_args(extra_workers int) !ParallelArgs {
 	mut fp := flag.new_flag_parser(os.args)
 	fp.application('vps')
 	fp.version('v0.1.0')
-	fp.limit_free_args(0, 0)?
+	fp.limit_free_args(0, 0)!
 	fp.description('This is a pendulum simulation written in pure V')
 	fp.skip_executable()
 
@@ -117,7 +117,7 @@ fn parse_parallel_args(extra_workers int) ?ParallelArgs {
 
 	fp.finalize() or {
 		println(fp.usage())
-		return none
+		return error('none')
 	}
 
 	params := sim.sim_params(

examples/pendulum-simulation/modules/sim/img/ppm.v

@@ -39,34 +39,34 @@ mut:
 	cache_size int
 }
 
-pub fn ppm_writer_for_fname(fname string, settings ImageSettings) ?&PPMWriter {
+pub fn ppm_writer_for_fname(fname string, settings ImageSettings) !&PPMWriter {
 	mut writer := &PPMWriter{
 		cache_size: settings.cache_size
 		cache: []u8{cap: settings.cache_size}
 	}
-	writer.start_for_file(fname, settings)?
+	writer.start_for_file(fname, settings)!
 	return writer
 }
 
-pub fn (mut writer PPMWriter) start_for_file(fname string, settings ImageSettings) ? {
-	writer.file = os.create(fname)?
-	writer.file.writeln('P6 $settings.width $settings.height 255')?
+pub fn (mut writer PPMWriter) start_for_file(fname string, settings ImageSettings) ! {
+	writer.file = os.create(fname)!
+	writer.file.writeln('P6 $settings.width $settings.height 255')!
 }
 
-pub fn (mut writer PPMWriter) handle_pixel(p gx.Color) ? {
+pub fn (mut writer PPMWriter) handle_pixel(p gx.Color) ! {
 	if writer.cache.len >= writer.cache_size {
-		writer.write()?
-		writer.flush()?
+		writer.write()!
+		writer.flush()!
 	}
 	writer.cache << [p.r, p.g, p.b]
 }
 
-pub fn (mut writer PPMWriter) flush() ? {
+pub fn (mut writer PPMWriter) flush() ! {
 	writer.cache.clear()
 }
 
-pub fn (mut writer PPMWriter) write() ? {
-	writer.file.write(writer.cache)?
+pub fn (mut writer PPMWriter) write() ! {
+	writer.file.write(writer.cache)!
 }
 
 pub fn (mut writer PPMWriter) close() {

examples/pendulum-simulation/modules/sim/img/writer.v

@@ -29,7 +29,7 @@ pub fn new_image_writer(mut writer PPMWriter, settings ImageSettings) &ImageWrit
 	}
 }
 
-pub fn (mut iw ImageWritter) handle(result sim.SimResult) ?int {
+pub fn (mut iw ImageWritter) handle(result sim.SimResult) !int {
 	total_pixels := iw.settings.width * iw.settings.height
 
 	// find the closest magnet
@@ -46,7 +46,7 @@ pub fn (mut iw ImageWritter) handle(result sim.SimResult) ?int {
 
 	if iw.current_index == total_pixels {
 		iw.writer.write() or { panic('Could not write image') }
-		return none
+		return error('none')
 	}
 
 	return iw.current_index

examples/pendulum-simulation/modules/sim/runner.v

@@ -3,11 +3,11 @@ module sim
 import benchmark
 import term
 
-pub type SimRequestHandler = fn (request &SimRequest) ?
+pub type SimRequestHandler = fn (request &SimRequest) !
 
-pub type SimStartHandler = fn () ?
+pub type SimStartHandler = fn () !
 
-pub type SimFinishHandler = fn () ?
+pub type SimFinishHandler = fn () !
 
 pub const (
 	default_width  = 600

examples/pendulum-simulation/parallel.v

@@ -6,7 +6,7 @@ import sim.args as simargs
 import sim.img
 
 fn main() {
-	args := simargs.parse_args()? as simargs.ParallelArgs
+	args := simargs.parse_args()! as simargs.ParallelArgs
 
 	img_settings := img.image_settings_from_grid(args.grid)
 
@@ -17,7 +17,7 @@ fn main() {
 	request_chan := chan &sim.SimRequest{cap: args.workers}
 	result_chan := chan &sim.SimResult{cap: args.workers}
 
-	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)?
+	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)!
 	mut image_writer := img.new_image_writer(mut writer, img_settings)
 
 	mut workers := []thread{cap: args.workers}

examples/pendulum-simulation/parallel_with_iw.v

@@ -6,14 +6,14 @@ import sim.args as simargs
 import sim.img
 
 fn main() {
-	args := simargs.parse_args(extra_workers: 1)? as simargs.ParallelArgs
+	args := simargs.parse_args(extra_workers: 1)! as simargs.ParallelArgs
 
 	img_settings := img.image_settings_from_grid(args.grid)
 
 	request_chan := chan &sim.SimRequest{cap: args.workers}
 	result_chan := chan &sim.SimResult{cap: args.workers}
 
-	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)?
+	mut writer := img.ppm_writer_for_fname(args.filename, img_settings)!
 
 	mut workers := []thread{cap: args.workers + 1}
 	mut bmark := benchmark.start()
@@ -39,7 +39,7 @@ fn main() {
 
 	workers << go img.image_worker(mut writer, result_chan, img_settings)
 
-	handle_request := fn [request_chan] (request &sim.SimRequest) ? {
+	handle_request := fn [request_chan] (request &sim.SimRequest) ! {
 		request_chan <- request
 	}
 

examples/pendulum-simulation/sequential.v

@@ -6,19 +6,19 @@ import sim.args as simargs
 import sim.img
 
 fn main() {
-	args := simargs.parse_args(sequential: true)? as simargs.SequentialArgs
+	args := simargs.parse_args(sequential: true)! as simargs.SequentialArgs
 
 	mut bmark := benchmark.start()
 	defer {
 		bmark.measure(@FN)
 	}
 
-	mut writer := img.ppm_writer_for_fname(args.filename, img.image_settings_from_grid(args.grid))?
+	mut writer := img.ppm_writer_for_fname(args.filename, img.image_settings_from_grid(args.grid))!
 	defer {
 		writer.close()
 	}
 
-	handle_request := fn [mut writer] (request &sim.SimRequest) ? {
+	handle_request := fn [mut writer] (request &sim.SimRequest) ! {
 		result := sim.compute_result(request)
 		pixel := img.compute_pixel(result)
 		return writer.handle_pixel(pixel)
@@ -26,5 +26,5 @@ fn main() {
 
 	sim.run(args.params, grid: args.grid, on_request: sim.SimRequestHandler(handle_request))
 
-	writer.write()?
+	writer.write()!
 }

examples/tcp_echo_server.v

@@ -9,11 +9,11 @@ import net
 // telnet 127.0.0.1 12345
 
 fn main() {
-	mut server := net.listen_tcp(.ip6, ':12345')?
-	laddr := server.addr()?
+	mut server := net.listen_tcp(.ip6, ':12345')!
+	laddr := server.addr()!
 	eprintln('Listen on $laddr ...')
 	for {
-		mut socket := server.accept()?
+		mut socket := server.accept()!
 		go handle_client(mut socket)
 	}
 }

examples/tcp_notify_echo_server.v

@@ -14,21 +14,21 @@ fn main() {
 	}
 
 	// create TCP listener
-	mut listener := net.listen_tcp(.ip, 'localhost:9001')?
+	mut listener := net.listen_tcp(.ip, 'localhost:9001')!
 	defer {
 		listener.close() or {}
 	}
-	addr := listener.addr()?
+	addr := listener.addr()!
 	eprintln('Listening on $addr')
 	eprintln('Type `stop` to stop the server')
 
 	// create file descriptor notifier
-	mut notifier := notify.new()?
+	mut notifier := notify.new()!
 	defer {
 		notifier.close() or {}
 	}
-	notifier.add(os.stdin().fd, .read)?
-	notifier.add(listener.sock.handle, .read)?
+	notifier.add(os.stdin().fd, .read)!
+	notifier.add(listener.sock.handle, .read)!
 
 	for {
 		for event in notifier.wait(time.infinite) {

examples/viewer/file_scan.v

@@ -150,10 +150,10 @@ fn (item_list Item_list) get_file_path() string {
 * Scan functions
 *
 ******************************************************************************/
-fn (mut item_list Item_list) scan_folder(path string, in_index int) ? {
+fn (mut item_list Item_list) scan_folder(path string, in_index int) ! {
 	println('Scanning [$path]')
 	mut folder_list := []string{}
-	lst := os.ls(path)?
+	lst := os.ls(path)!
 
 	// manage the single files
 	for c, x in lst {
@@ -171,7 +171,7 @@ fn (mut item_list Item_list) scan_folder(path string, in_index int) ? {
 			if ext == .zip {
 				item.i_type = .zip
 				item_list.lst << item
-				item_list.scan_zip(pt, item_list.lst.len - 1)?
+				item_list.scan_zip(pt, item_list.lst.len - 1)!
 				continue
 			}
 			if is_image(ext) == true {
@@ -194,7 +194,7 @@ fn (mut item_list Item_list) scan_folder(path string, in_index int) ? {
 			i_type: .folder
 		}
 		item_list.lst << item
-		item_list.scan_folder(pt, item_list.lst.len - 1)?
+		item_list.scan_folder(pt, item_list.lst.len - 1)!
 	}
 	// println(item_list.lst.len)
 	// println("==================================")

examples/viewer/zip_container.v

@@ -11,14 +11,14 @@
 import sokol.gfx
 import szip
 
-fn (mut il Item_list) scan_zip(path string, in_index int) ? {
+fn (mut il Item_list) scan_zip(path string, in_index int) ! {
 	println('Scanning ZIP [$path]')
-	mut zp := szip.open(path, szip.CompressionLevel.no_compression, szip.OpenMode.read_only)?
-	n_entries := zp.total()?
+	mut zp := szip.open(path, szip.CompressionLevel.no_compression, szip.OpenMode.read_only)!
+	n_entries := zp.total()!
 	// println(n_entries)
 	for index in 0 .. n_entries {
-		zp.open_entry_by_index(index)?
-		is_dir := zp.is_dir()?
+		zp.open_entry_by_index(index)!
+		is_dir := zp.is_dir()!
 		name := zp.name()
 		size := zp.size()
 		// println("$index ${name} ${size:10} $is_dir")
@@ -47,7 +47,7 @@ fn (mut il Item_list) scan_zip(path string, in_index int) ? {
 	zp.close()
 }
 
-fn (mut app App) load_texture_from_zip() ?(gfx.Image, int, int) {
+fn (mut app App) load_texture_from_zip() !(gfx.Image, int, int) {
 	item := app.item_list.lst[app.item_list.item_index]
 	// println("Load from zip [${item.path}]")
 
@@ -58,15 +58,15 @@ fn (mut app App) load_texture_from_zip() ?(gfx.Image, int, int) {
 		}
 		app.zip_index = item.container_index
 		// println("Opening the zip [${item.path}]")
-		app.zip = szip.open(item.path, szip.CompressionLevel.no_compression, szip.OpenMode.read_only)?
+		app.zip = szip.open(item.path, szip.CompressionLevel.no_compression, szip.OpenMode.read_only)!
 	}
 	// println("Now get the image")
-	app.zip.open_entry_by_index(item.container_item_index)?
+	app.zip.open_entry_by_index(item.container_item_index)!
 	zip_entry_size := int(item.size)
 
 	app.resize_buf_if_needed(zip_entry_size)
 
-	app.zip.read_entry_buf(app.mem_buf, app.mem_buf_size)?
+	app.zip.read_entry_buf(app.mem_buf, app.mem_buf_size)!
 	app.zip.close_entry()
 	return app.load_texture_from_buffer(app.mem_buf, zip_entry_size)
 }

examples/vweb/vweb_assets/vweb_assets.v

@@ -17,7 +17,7 @@ fn main() {
 	mut app := &App{}
 	app.serve_static('/favicon.ico', 'favicon.ico')
 	// Automatically make available known static mime types found in given directory.
-	os.chdir(os.dir(os.executable()))?
+	os.chdir(os.dir(os.executable()))!
 	app.handle_static('assets', true)
 	vweb.run(app, port)
 }

examples/websocket/client-server/client.v

@@ -8,7 +8,7 @@ import term
 // it connects to the server who will broadcast your messages
 // to all other connected clients
 fn main() {
-	mut ws := start_client()?
+	mut ws := start_client()!
 	println(term.green('client $ws.id ready'))
 	println('Write message and enter to send...')
 	for {
@@ -16,7 +16,7 @@ fn main() {
 		if line == '' {
 			break
 		}
-		ws.write_string(line)?
+		ws.write_string(line)!
 	}
 	ws.close(1000, 'normal') or { println(term.red('panicing $err')) }
 	unsafe {
@@ -24,23 +24,23 @@ fn main() {
 	}
 }
 
-fn start_client() ?&websocket.Client {
-	mut ws := websocket.new_client('ws://localhost:30000')?
+fn start_client() !&websocket.Client {
+	mut ws := websocket.new_client('ws://localhost:30000')!
 	// mut ws := websocket.new_client('wss://echo.websocket.org:443')?
 	// use on_open_ref if you want to send any reference object
-	ws.on_open(fn (mut ws websocket.Client) ? {
+	ws.on_open(fn (mut ws websocket.Client) ! {
 		println(term.green('websocket connected to the server and ready to send messages...'))
 	})
 	// use on_error_ref if you want to send any reference object
-	ws.on_error(fn (mut ws websocket.Client, err string) ? {
+	ws.on_error(fn (mut ws websocket.Client, err string) ! {
 		println(term.red('error: $err'))
 	})
 	// use on_close_ref if you want to send any reference object
-	ws.on_close(fn (mut ws websocket.Client, code int, reason string) ? {
+	ws.on_close(fn (mut ws websocket.Client, code int, reason string) ! {
 		println(term.green('the connection to the server successfully closed'))
 	})
 	// on new messages from other clients, display them in blue text
-	ws.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ? {
+	ws.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ! {
 		if msg.payload.len > 0 {
 			message := msg.payload.bytestr()
 			println(term.blue('$message'))

examples/websocket/client-server/server.v

@@ -6,24 +6,24 @@ import term
 // this server accepts client connections and broadcast all messages to other connected clients
 fn main() {
 	println('press ctrl-c to quit...')
-	start_server()?
+	start_server()!
 }
 
-fn start_server() ? {
+fn start_server() ! {
 	mut s := websocket.new_server(.ip6, 30000, '')
 	// Make that in execution test time give time to execute at least one time
 	s.ping_interval = 100
-	s.on_connect(fn (mut s websocket.ServerClient) ?bool {
+	s.on_connect(fn (mut s websocket.ServerClient) !bool {
 		// Here you can look att the client info and accept or not accept
 		// just returning a true/false
 		if s.resource_name != '/' {
 			return false
 		}
 		return true
-	})?
+	})!
 
 	// on_message_ref, broadcast all incoming messages to all clients except the one sent it
-	s.on_message_ref(fn (mut ws websocket.Client, msg &websocket.Message, mut m websocket.Server) ? {
+	s.on_message_ref(fn (mut ws websocket.Client, msg &websocket.Message, mut m websocket.Server) ! {
 		// for _, cli in m.clients {
 		for i, _ in m.clients {
 			mut c := m.clients[i]
@@ -33,7 +33,7 @@ fn start_server() ? {
 		}
 	}, s)
 
-	s.on_close(fn (mut ws websocket.Client, code int, reason string) ? {
+	s.on_close(fn (mut ws websocket.Client, code int, reason string) ! {
 		println(term.green('client ($ws.id) closed connection'))
 	})
 	s.listen() or { println(term.red('error on server listen: $err')) }

examples/websocket/ping.v

@@ -6,27 +6,27 @@ import net.websocket
 fn main() {
 	go start_server()
 	time.sleep(100 * time.millisecond)
-	start_client()?
+	start_client()!
 }
 
 // start_server starts the websocket server, it receives messages
 // and send it back to the client that sent it
-fn start_server() ? {
+fn start_server() ! {
 	mut s := websocket.new_server(.ip6, 30000, '')
 	// Make that in execution test time give time to execute at least one time
 	s.ping_interval = 100
-	s.on_connect(fn (mut s websocket.ServerClient) ?bool {
+	s.on_connect(fn (mut s websocket.ServerClient) !bool {
 		// Here you can look att the client info and accept or not accept
 		// just returning a true/false
 		if s.resource_name != '/' {
 			return false
 		}
 		return true
-	})?
-	s.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ? {
+	})!
+	s.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ! {
 		ws.write(msg.payload, msg.opcode) or { panic(err) }
 	})
-	s.on_close(fn (mut ws websocket.Client, code int, reason string) ? {
+	s.on_close(fn (mut ws websocket.Client, code int, reason string) ! {
 		// println('client ($ws.id) closed connection')
 	})
 	s.listen() or { println('error on server listen: $err') }
@@ -37,23 +37,23 @@ fn start_server() ? {
 
 // start_client starts the websocket client, it writes a message to
 // the server and prints all the messages received
-fn start_client() ? {
-	mut ws := websocket.new_client('ws://localhost:30000')?
+fn start_client() ! {
+	mut ws := websocket.new_client('ws://localhost:30000')!
 	// mut ws := websocket.new_client('wss://echo.websocket.org:443')?
 	// use on_open_ref if you want to send any reference object
-	ws.on_open(fn (mut ws websocket.Client) ? {
+	ws.on_open(fn (mut ws websocket.Client) ! {
 		println('open!')
 	})
 	// use on_error_ref if you want to send any reference object
-	ws.on_error(fn (mut ws websocket.Client, err string) ? {
+	ws.on_error(fn (mut ws websocket.Client, err string) ! {
 		println('error: $err')
 	})
 	// use on_close_ref if you want to send any reference object
-	ws.on_close(fn (mut ws websocket.Client, code int, reason string) ? {
+	ws.on_close(fn (mut ws websocket.Client, code int, reason string) ! {
 		println('closed')
 	})
 	// use on_message_ref if you want to send any reference object
-	ws.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ? {
+	ws.on_message(fn (mut ws websocket.Client, msg &websocket.Message) ! {
 		if msg.payload.len > 0 {
 			message := msg.payload.bytestr()
 			println('client got type: $msg.opcode payload:\n$message')
@@ -72,7 +72,7 @@ fn start_client() ? {
 	}
 }
 
-fn write_echo(mut ws websocket.Client) ? {
+fn write_echo(mut ws websocket.Client) ! {
 	message := 'echo this'
 	for i := 0; i <= 10; i++ {
 		// Server will send pings every 30 seconds

vlib/builtin/string.v

@@ -624,7 +624,7 @@ pub fn (s string) u64() u64 {
 // This method directly exposes the `parse_int` function from `strconv`
 // as a method on `string`. For more advanced features,
 // consider calling `strconv.common_parse_int` directly.
-pub fn (s string) parse_uint(_base int, _bit_size int) ?u64 {
+pub fn (s string) parse_uint(_base int, _bit_size int) !u64 {
 	return strconv.parse_uint(s, _base, _bit_size)
 }
 
@@ -644,7 +644,7 @@ pub fn (s string) parse_uint(_base int, _bit_size int) ?u64 {
 // This method directly exposes the `parse_uint` function from `strconv`
 // as a method on `string`. For more advanced features,
 // consider calling `strconv.common_parse_uint` directly.
-pub fn (s string) parse_int(_base int, _bit_size int) ?i64 {
+pub fn (s string) parse_int(_base int, _bit_size int) !i64 {
 	return strconv.parse_int(s, _base, _bit_size)
 }
 

vlib/dl/dl.v

@@ -28,7 +28,7 @@ pub fn get_libname(libname string) string {
 
 // open_opt - loads the dynamic shared object.
 // Unlike open, open_opt return an option.
-pub fn open_opt(filename string, flags int) ?voidptr {
+pub fn open_opt(filename string, flags int) !voidptr {
 	shared_object_handle := open(filename, flags)
 	if shared_object_handle == 0 {
 		e := dlerror()
@@ -39,7 +39,7 @@ pub fn open_opt(filename string, flags int) ?voidptr {
 
 // sym_opt returns the address of a symbol in a given shared object, if found.
 // Unlike sym, sym_opt returns an option.
-pub fn sym_opt(shared_object_handle voidptr, symbol string) ?voidptr {
+pub fn sym_opt(shared_object_handle voidptr, symbol string) !voidptr {
 	sym_handle := sym(shared_object_handle, symbol)
 	if sym_handle == 0 {
 		e := dlerror()

vlib/flag/flag.v

@@ -71,7 +71,7 @@ pub fn (af []Flag) str() string {
 // That structure is created with `mut parser := flag.new_flag_parser(os.args)`,
 // The returned instance can be further customised by calling various methods,
 // for specifying the accepted options and their values. The user should finally
-// call `rest := parser.finalize()?` to get the rest of the non optional arguments
+// call `rest := parser.finalize()!` to get the rest of the non optional arguments
 // (if there are any left).
 pub struct FlagParser {
 pub:
@@ -278,7 +278,7 @@ fn (mut fs FlagParser) parse_value(longhand string, shorthand u8) []string {
 // special: it is allowed to define bool flags without value
 // -> '--flag' is parsed as true
 // -> '--flag' is equal to '--flag=true'
-fn (mut fs FlagParser) parse_bool_value(longhand string, shorthand u8) ?string {
+fn (mut fs FlagParser) parse_bool_value(longhand string, shorthand u8) !string {
 	{
 		full := '--$longhand'
 		for i, arg in fs.args {
@@ -317,7 +317,7 @@ fn (mut fs FlagParser) parse_bool_value(longhand string, shorthand u8) ?string {
 // bool_opt returns an option with the bool value of the given command line flag, named `name`.
 // It returns an error, when the flag is not given by the user.
 // This version supports abbreviations.
-pub fn (mut fs FlagParser) bool_opt(name string, abbr u8, usage string) ?bool {
+pub fn (mut fs FlagParser) bool_opt(name string, abbr u8, usage string) !bool {
 	mut res := false
 	{
 		fs.add_flag(name, abbr, usage, '<bool>')
@@ -354,7 +354,7 @@ pub fn (mut fs FlagParser) int_multi(name string, abbr u8, usage string) []int {
 // int_opt returns an option with the integer value, associated with the flag in `name`.
 // When the flag is not given by the user, it returns an error.
 // This version supports abbreviations.
-pub fn (mut fs FlagParser) int_opt(name string, abbr u8, usage string) ?int {
+pub fn (mut fs FlagParser) int_opt(name string, abbr u8, usage string) !int {
 	mut res := 0
 	{
 		fs.add_flag(name, abbr, usage, '<int>')
@@ -393,7 +393,7 @@ pub fn (mut fs FlagParser) float_multi(name string, abbr u8, usage string) []f64
 // float_opt returns an option with the floating point value, associated with the flag in `name`.
 // When the flag is not given by the user, it returns an error.
 // This version supports abbreviations.
-pub fn (mut fs FlagParser) float_opt(name string, abbr u8, usage string) ?f64 {
+pub fn (mut fs FlagParser) float_opt(name string, abbr u8, usage string) !f64 {
 	mut res := 0.0
 	{
 		fs.add_flag(name, abbr, usage, '<float>')
@@ -426,7 +426,7 @@ pub fn (mut fs FlagParser) string_multi(name string, abbr u8, usage string) []st
 // string_opt returns an option with the string value, associated with the flag in `name`.
 // When the flag is not given by the user, it returns an error.
 // This version supports abbreviations.
-pub fn (mut fs FlagParser) string_opt(name string, abbr u8, usage string) ?string {
+pub fn (mut fs FlagParser) string_opt(name string, abbr u8, usage string) !string {
 	mut res := ''
 	{
 		fs.add_flag(name, abbr, usage, '<string>')
@@ -451,7 +451,7 @@ pub fn (mut fs FlagParser) string(name string, abbr u8, sdefault string, usage s
 // limit_free_args_to_at_least restricts the list of free arguments (non options) to be
 // at least `n` in length. If the user gives less free arguments to the program,
 // the parser will return an error.
-pub fn (mut fs FlagParser) limit_free_args_to_at_least(n int) ? {
+pub fn (mut fs FlagParser) limit_free_args_to_at_least(n int) ! {
 	if n > flag.max_args_number {
 		return error('flag.limit_free_args_to_at_least expect n to be smaller than $flag.max_args_number')
 	}
@@ -464,7 +464,7 @@ pub fn (mut fs FlagParser) limit_free_args_to_at_least(n int) ? {
 // limit_free_args_to_exactly restricts the list of free arguments (non options) to be
 // at exactly `n` in length. If the user gives more or less free arguments to the program,
 // the parser will return an error.
-pub fn (mut fs FlagParser) limit_free_args_to_exactly(n int) ? {
+pub fn (mut fs FlagParser) limit_free_args_to_exactly(n int) ! {
 	if n > flag.max_args_number {
 		return error('flag.limit_free_args_to_exactly expect n to be smaller than $flag.max_args_number')
 	}
@@ -478,7 +478,7 @@ pub fn (mut fs FlagParser) limit_free_args_to_exactly(n int) ? {
 // limit_free_args restricts the list of free arguments (non options) to be between
 // `min` and `max` in length. If the user gives more or less free arguments to the program,
 // the parser will return an error.
-pub fn (mut fs FlagParser) limit_free_args(min int, max int) ? {
+pub fn (mut fs FlagParser) limit_free_args(min int, max int) ! {
 	if min > max {
 		return error('flag.limit_free_args expect min < max, got $min >= $max')
 	}
@@ -578,7 +578,7 @@ pub fn (fs FlagParser) usage() string {
 
 // find_existing_flag looks up the given flag by name, and returns
 // it, if it was found in the FlagParser. If it was not, it returns an error.
-fn (mut fs FlagParser) find_existing_flag(fname string) ?Flag {
+fn (mut fs FlagParser) find_existing_flag(fname string) !Flag {
 	for f in fs.flags {
 		if f.name == fname {
 			return f
@@ -614,7 +614,7 @@ fn (mut fs FlagParser) handle_builtin_options() {
 // The remaining arguments are returned in the same order they are
 // defined on the command line. If additional flags are found, i.e.
 // (things starting with '--' or '-'), it returns an error.
-pub fn (mut fs FlagParser) finalize() ?[]string {
+pub fn (mut fs FlagParser) finalize() ![]string {
 	fs.handle_builtin_options()
 	mut remaining := fs.args.clone()
 	if !fs.allow_unknown_args {

vlib/flag/flag_test.v

@@ -153,9 +153,9 @@ fn test_finalize_returns_error_for_unknown_flags_short() {
 	assert finalized.len < 0 // expect error to be returned
 }
 
-fn test_allow_to_build_usage_message() ? {
+fn test_allow_to_build_usage_message() {
 	mut fp := flag.new_flag_parser([])
-	fp.limit_free_args(1, 4)?
+	fp.limit_free_args(1, 4)!
 	fp.application('flag_tool')
 	fp.version('v0.0.0')
 	fp.description('some short information about this tool')
@@ -194,9 +194,9 @@ fn test_if_no_options_given_usage_message_does_not_contain_options() {
 	assert !fp.usage().contains('Options:')
 }
 
-fn test_free_args_could_be_limited() ? {
+fn test_free_args_could_be_limited() {
 	mut fp1 := flag.new_flag_parser(['a', 'b', 'c'])
-	fp1.limit_free_args(1, 4)?
+	fp1.limit_free_args(1, 4)!
 	args := fp1.finalize() or {
 		assert false
 		return
@@ -206,9 +206,9 @@ fn test_free_args_could_be_limited() ? {
 	assert args[2] == 'c'
 }
 
-fn test_error_for_to_few_free_args() ? {
+fn test_error_for_to_few_free_args() {
 	mut fp1 := flag.new_flag_parser(['a', 'b', 'c'])
-	fp1.limit_free_args(5, 6)?
+	fp1.limit_free_args(5, 6)!
 	args := fp1.finalize() or {
 		assert err.msg().starts_with('Expected at least 5 arguments')
 		return
@@ -216,9 +216,9 @@ fn test_error_for_to_few_free_args() ? {
 	assert args.len < 0 // expect an error and need to use args
 }
 
-fn test_error_for_to_much_free_args() ? {
+fn test_error_for_to_much_free_args() {
 	mut fp1 := flag.new_flag_parser(['a', 'b', 'c'])
-	fp1.limit_free_args(1, 2)?
+	fp1.limit_free_args(1, 2)!
 	args := fp1.finalize() or {
 		assert err.msg().starts_with('Expected at most 2 arguments')
 		return
@@ -226,9 +226,9 @@ fn test_error_for_to_much_free_args() ? {
 	assert args.len < 0 // expect an error and need to use args
 }
 
-fn test_could_expect_no_free_args() ? {
+fn test_could_expect_no_free_args() {
 	mut fp1 := flag.new_flag_parser(['a'])
-	fp1.limit_free_args(0, 0)?
+	fp1.limit_free_args(0, 0)!
 	args := fp1.finalize() or {
 		assert err.msg().starts_with('Expected no arguments')
 		return
@@ -383,7 +383,7 @@ fn test_optional_flags() {
 	assert b == 'some_default_value'
 }
 
-fn test_dashdash_acts_as_parser_full_stop() ? {
+fn test_dashdash_acts_as_parser_full_stop() {
 	mut fp := flag.new_flag_parser(['-b', '5', '--', '-d', '-x', '-b', '4', '-a', '-c', 'hello',
 		'some', 'other', 'parameters'])
 	a := fp.bool_opt('a-bool-flag', `a`, '') or { false }
@@ -392,17 +392,17 @@ fn test_dashdash_acts_as_parser_full_stop() ? {
 	assert a == false
 	assert b == 5
 	assert c == 'default'
-	args := fp.finalize()?
+	args := fp.finalize()!
 	assert args.len > 0
 	assert args[0] != '--'
 	assert args == ['-d', '-x', '-b', '4', '-a', '-c', 'hello', 'some', 'other', 'parameters']
 }
 
-fn test_dashdash_acts_as_parser_full_stop_dashdash_at_end() ? {
+fn test_dashdash_acts_as_parser_full_stop_dashdash_at_end() {
 	mut fp := flag.new_flag_parser(['-b', '5', '-b', '4', 'other', 'params', '--'])
 	b := fp.int_multi('an-int-flag', `b`, '')
 	assert b == [5, 4]
-	args := fp.finalize()?
+	args := fp.finalize()!
 	assert args.len > 0
 }
 

vlib/io/buffered_reader.v

@@ -107,9 +107,9 @@ pub fn (r BufferedReader) end_of_stream() bool {
 // read_line attempts to read a line from the buffered reader
 // it will read until it finds a new line character (\n) or
 // the end of stream
-pub fn (mut r BufferedReader) read_line() ?string {
+pub fn (mut r BufferedReader) read_line() !string {
 	if r.end_of_stream {
-		return none
+		return error('none')
 	}
 	mut line := []u8{}
 	for {
@@ -119,7 +119,7 @@ pub fn (mut r BufferedReader) read_line() ?string {
 				// We are at the end of the stream
 				if line.len == 0 {
 					// we had nothing so return nothing
-					return none
+					return error('none')
 				}
 				return line.bytestr()
 			}
@@ -144,5 +144,5 @@ pub fn (mut r BufferedReader) read_line() ?string {
 		line << r.buf[r.offset..i]
 		r.offset = i
 	}
-	return none
+	return error('none')
 }

vlib/io/io.v

@@ -4,7 +4,7 @@ const (
 	buf_max_len = 1024
 )
 
-pub fn cp(mut src Reader, mut dst Writer) ? {
+pub fn cp(mut src Reader, mut dst Writer) ! {
 	mut buf := []u8{len: io.buf_max_len}
 	for {
 		len := src.read(mut buf) or { break }

vlib/io/io_cp_test.v

@@ -1,13 +1,13 @@
 import io
 import os
 
-fn test_cp() ? {
+fn test_cp() {
 	mut f := os.open(@FILE) or { panic(err) }
 	defer {
 		f.close()
 	}
 	mut r := io.new_buffered_reader(reader: f)
 	mut stdout := os.stdout()
-	io.cp(mut r, mut stdout)?
+	io.cp(mut r, mut stdout)!
 	assert true
 }

vlib/io/io_test.v

@@ -21,9 +21,9 @@ fn (mut b Buf) read(mut buf []u8) !int {
 	return n
 }
 
-fn (mut w Writ) write(buf []u8) ?int {
+fn (mut w Writ) write(buf []u8) !int {
 	if buf.len <= 0 {
-		return none
+		return error('none')
 	}
 	w.bytes << buf
 	return buf.len

vlib/io/multi_writer.v

@@ -22,9 +22,9 @@ pub mut:
 // written. If any writer fails to write the full length an error is returned
 // and writing to other writers stops. If any writer returns an error the error
 // is returned immediately and writing to other writers stops.
-pub fn (mut m MultiWriter) write(buf []u8) ?int {
+pub fn (mut m MultiWriter) write(buf []u8) !int {
 	for mut w in m.writers {
-		n := w.write(buf)?
+		n := w.write(buf)!
 		if n != buf.len {
 			return error('io: incomplete write to writer of MultiWriter')
 		}

vlib/io/multi_writer_test.v

@@ -43,7 +43,7 @@ pub mut:
 	bytes []u8
 }
 
-fn (mut w TestWriter) write(buf []u8) ?int {
+fn (mut w TestWriter) write(buf []u8) !int {
 	w.bytes << buf
 	return buf.len
 }
@@ -53,7 +53,7 @@ pub mut:
 	bytes []u8
 }
 
-fn (mut w TestIncompleteWriter) write(buf []u8) ?int {
+fn (mut w TestIncompleteWriter) write(buf []u8) !int {
 	b := buf[..buf.len - 1]
 	w.bytes << b
 	return b.len
@@ -61,6 +61,6 @@ fn (mut w TestIncompleteWriter) write(buf []u8) ?int {
 
 struct TestErrorWriter {}
 
-fn (mut w TestErrorWriter) write(buf []u8) ?int {
+fn (mut w TestErrorWriter) write(buf []u8) !int {
 	return error('error writer errored')
 }

vlib/io/reader.v

@@ -44,7 +44,7 @@ mut:
 
 // read_all reads all bytes from a reader until either a 0 length read
 // or if read_to_end_of_stream is true then the end of the stream (`none`)
-pub fn read_all(config ReadAllConfig) ?[]u8 {
+pub fn read_all(config ReadAllConfig) ![]u8 {
 	mut r := config.reader
 	read_till_eof := config.read_to_end_of_stream
 
@@ -65,11 +65,11 @@ pub fn read_all(config ReadAllConfig) ?[]u8 {
 
 // read_any reads any available bytes from a reader
 // (until the reader returns a read of 0 length)
-pub fn read_any(mut r Reader) ?[]u8 {
+pub fn read_any(mut r Reader) ![]u8 {
 	mut b := []u8{len: io.read_all_len}
 	mut read := 0
 	for {
-		new_read := r.read(mut b[read..]) or { return none }
+		new_read := r.read(mut b[read..]) or { return error('none') }
 		read += new_read
 		if new_read == 0 {
 			break
@@ -83,5 +83,5 @@ pub fn read_any(mut r Reader) ?[]u8 {
 
 // RandomReader represents a stream of data that can be read from at a random location
 pub interface RandomReader {
-	read_from(pos u64, mut buf []u8) ?int
+	read_from(pos u64, mut buf []u8) !int
 }

vlib/io/readerwriter.v

@@ -18,7 +18,7 @@ pub fn (mut r ReaderWriterImpl) read(mut buf []u8) !int {
 	return r.r.read(mut buf)
 }
 
-pub fn (mut r ReaderWriterImpl) write(buf []u8) ?int {
+pub fn (mut r ReaderWriterImpl) write(buf []u8) !int {
 	return r.w.write(buf)
 }
 

vlib/io/util/util.v

@@ -14,7 +14,7 @@ pub struct TempFileOptions {
 }
 
 // temp_file returns an uniquely named, open, writable, `os.File` and it's path
-pub fn temp_file(tfo TempFileOptions) ?(os.File, string) {
+pub fn temp_file(tfo TempFileOptions) !(os.File, string) {
 	mut d := tfo.path
 	if d == '' {
 		d = os.temp_dir()
@@ -47,7 +47,7 @@ pub struct TempDirOptions {
 }
 
 // temp_dir returns an uniquely named, writable, directory path
-pub fn temp_dir(tdo TempFileOptions) ?string {
+pub fn temp_dir(tdo TempFileOptions) !string {
 	mut d := tdo.path
 	if d == '' {
 		d = os.temp_dir()

vlib/io/writer.v

@@ -3,11 +3,11 @@ module io
 // Writer represents a stream of data that can be wrote to
 pub interface Writer {
 mut:
-	write(buf []u8) ?int
+	write(buf []u8) !int
 }
 
 // RandomWriter represents a stream of data that can be wrote to
 // at a random pos
 pub interface RandomWriter {
-	write_to(pos u64, buf []u8) ?int
+	write_to(pos u64, buf []u8) !int
 }

vlib/net/address.v

@@ -44,15 +44,15 @@ fn new_ip(port u16, addr [4]u8) Addr {
 	return a
 }
 
-fn temp_unix() ?Addr {
+fn temp_unix() !Addr {
 	// create a temp file to get a filename
 	// close it
 	// remove it
 	// then reuse the filename
-	mut file, filename := util.temp_file()?
+	mut file, filename := util.temp_file()!
 	file.close()
-	os.rm(filename)?
-	addrs := resolve_addrs(filename, .unix, .udp)?
+	os.rm(filename)!
+	addrs := resolve_addrs(filename, .unix, .udp)!
 	return addrs[0]
 }
 
@@ -114,7 +114,7 @@ fn (a Addr) len() u32 {
 	}
 }
 
-pub fn resolve_addrs(addr string, family AddrFamily, @type SocketType) ?[]Addr {
+pub fn resolve_addrs(addr string, family AddrFamily, @type SocketType) ![]Addr {
 	match family {
 		.ip, .ip6, .unspec {
 			return resolve_ipaddrs(addr, family, @type)
@@ -143,9 +143,9 @@ pub fn resolve_addrs(addr string, family AddrFamily, @type SocketType) ?[]Addr {
 	}
 }
 
-pub fn resolve_addrs_fuzzy(addr string, @type SocketType) ?[]Addr {
+pub fn resolve_addrs_fuzzy(addr string, @type SocketType) ![]Addr {
 	if addr.len == 0 {
-		return none
+		return error('none')
 	}
 
 	// Use a small heuristic to figure out what address family this is
@@ -160,8 +160,8 @@ pub fn resolve_addrs_fuzzy(addr string, @type SocketType) ?[]Addr {
 	return resolve_addrs(addr, .unix, @type)
 }
 
-pub fn resolve_ipaddrs(addr string, family AddrFamily, typ SocketType) ?[]Addr {
-	address, port := split_address(addr)?
+pub fn resolve_ipaddrs(addr string, family AddrFamily, typ SocketType) ![]Addr {
+	address, port := split_address(addr)!
 
 	if addr[0] == `:` {
 		match family {
@@ -191,10 +191,10 @@ pub fn resolve_ipaddrs(addr string, family AddrFamily, typ SocketType) ?[]Addr {
 
 	// This might look silly but is recommended by MSDN
 	$if windows {
-		socket_error(0 - C.getaddrinfo(&char(address.str), &char(sport.str), &hints, &results))?
+		socket_error(0 - C.getaddrinfo(&char(address.str), &char(sport.str), &hints, &results))!
 	} $else {
 		x := C.getaddrinfo(&char(address.str), &char(sport.str), &hints, &results)
-		wrap_error(x)?
+		wrap_error(x)!
 	}
 
 	defer {

vlib/net/common.v

@@ -17,18 +17,18 @@ pub const no_timeout = time.Duration(0)
 pub const infinite_timeout = time.infinite
 
 // Shutdown shutsdown a socket and closes it
-fn shutdown(handle int) ? {
+fn shutdown(handle int) ! {
 	$if windows {
 		C.shutdown(handle, C.SD_BOTH)
-		socket_error(C.closesocket(handle))?
+		socket_error(C.closesocket(handle))!
 	} $else {
 		C.shutdown(handle, C.SHUT_RDWR)
-		socket_error(C.close(handle))?
+		socket_error(C.close(handle))!
 	}
 }
 
 // Select waits for an io operation (specified by parameter `test`) to be available
-fn @select(handle int, test Select, timeout time.Duration) ?bool {
+fn @select(handle int, test Select, timeout time.Duration) !bool {
 	set := C.fd_set{}
 
 	C.FD_ZERO(&set)
@@ -52,13 +52,13 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 
 	match test {
 		.read {
-			socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))?
+			socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))!
 		}
 		.write {
-			socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))?
+			socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))!
 		}
 		.except {
-			socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))?
+			socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))!
 		}
 	}
 
@@ -66,7 +66,7 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 }
 
 [inline]
-fn select_deadline(handle int, test Select, deadline time.Time) ?bool {
+fn select_deadline(handle int, test Select, deadline time.Time) !bool {
 	// if we have a 0 deadline here then the timeout that was passed was infinite...
 	infinite := deadline.unix_time() == 0
 	for infinite || time.now() <= deadline {
@@ -89,7 +89,7 @@ fn select_deadline(handle int, test Select, deadline time.Time) ?bool {
 }
 
 // wait_for_common wraps the common wait code
-fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ? {
+fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ! {
 	// Convert timeouts to deadlines
 	real_deadline := if timeout == net.infinite_timeout {
 		time.unix(0)
@@ -104,7 +104,7 @@ fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test S
 		time.now().add(timeout)
 	}
 
-	ready := select_deadline(handle, test, real_deadline)?
+	ready := select_deadline(handle, test, real_deadline)!
 
 	if ready {
 		return
@@ -114,11 +114,11 @@ fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test S
 }
 
 // wait_for_write waits for a write io operation to be available
-fn wait_for_write(handle int, deadline time.Time, timeout time.Duration) ? {
+fn wait_for_write(handle int, deadline time.Time, timeout time.Duration) ! {
 	return wait_for_common(handle, deadline, timeout, .write)
 }
 
 // wait_for_read waits for a read io operation to be available
-fn wait_for_read(handle int, deadline time.Time, timeout time.Duration) ? {
+fn wait_for_read(handle int, deadline time.Time, timeout time.Duration) ! {
 	return wait_for_common(handle, deadline, timeout, .read)
 }

vlib/net/errors.v

@@ -21,11 +21,11 @@ pub const (
 	err_connection_refused  = error_with_code('net: connection refused', errors_base + 10)
 )
 
-pub fn socket_error_message(potential_code int, s string) ?int {
+pub fn socket_error_message(potential_code int, s string) !int {
 	return socket_error(potential_code) or { return error('$err.msg(); $s') }
 }
 
-pub fn socket_error(potential_code int) ?int {
+pub fn socket_error(potential_code int) !int {
 	$if windows {
 		if potential_code < 0 {
 			last_error_int := C.WSAGetLastError()
@@ -43,7 +43,7 @@ pub fn socket_error(potential_code int) ?int {
 	return potential_code
 }
 
-pub fn wrap_error(error_code int) ? {
+pub fn wrap_error(error_code int) ! {
 	if error_code == 0 {
 		return
 	}
@@ -59,17 +59,17 @@ pub fn wrap_error(error_code int) ? {
 // connection termination and returns none
 // e.g. res := wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))?
 [inline]
-fn wrap_read_result(result int) ?int {
+fn wrap_read_result(result int) !int {
 	if result == 0 {
-		return none
+		return error('none')
 	}
 	return result
 }
 
 [inline]
-fn wrap_write_result(result int) ?int {
+fn wrap_write_result(result int) !int {
 	if result == 0 {
-		return none
+		return error('none')
 	}
 	return result
 }

vlib/net/ftp/ftp.v

@@ -42,7 +42,7 @@ mut:
 	port   int
 }
 
-fn (mut dtp DTP) read() ?[]u8 {
+fn (mut dtp DTP) read() ![]u8 {
 	mut data := []u8{}
 	mut buf := []u8{len: 1024}
 	for {
@@ -75,15 +75,15 @@ pub fn new() FTP {
 	return f
 }
 
-fn (mut zftp FTP) write(data string) ?int {
+fn (mut zftp FTP) write(data string) !int {
 	$if debug {
 		println('FTP.v >>> $data')
 	}
 	return zftp.conn.write('$data\r\n'.bytes())
 }
 
-fn (mut zftp FTP) read() ?(int, string) {
-	mut data := zftp.reader.read_line()?
+fn (mut zftp FTP) read() !(int, string) {
+	mut data := zftp.reader.read_line()!
 	$if debug {
 		println('FTP.v <<< $data')
 	}
@@ -93,7 +93,7 @@ fn (mut zftp FTP) read() ?(int, string) {
 	code := data[..3].int()
 	if data[3] == `-` {
 		for {
-			data = zftp.reader.read_line()?
+			data = zftp.reader.read_line()!
 			if data[..3].int() == code && data[3] != `-` {
 				break
 			}
@@ -103,10 +103,10 @@ fn (mut zftp FTP) read() ?(int, string) {
 }
 
 // connect establishes an FTP connection to the host at `ip` port 21.
-pub fn (mut zftp FTP) connect(ip string) ?bool {
-	zftp.conn = net.dial_tcp('$ip:21')?
+pub fn (mut zftp FTP) connect(ip string) !bool {
+	zftp.conn = net.dial_tcp('$ip:21')!
 	zftp.reader = io.new_buffered_reader(reader: zftp.conn)
-	code, _ := zftp.read()?
+	code, _ := zftp.read()!
 	if code == ftp.connected {
 		return true
 	}
@@ -114,14 +114,14 @@ pub fn (mut zftp FTP) connect(ip string) ?bool {
 }
 
 // login sends the "USER `user`" and "PASS `passwd`" commands to the remote host.
-pub fn (mut zftp FTP) login(user string, passwd string) ?bool {
+pub fn (mut zftp FTP) login(user string, passwd string) !bool {
 	zftp.write('USER $user') or {
 		$if debug {
 			println('ERROR sending user')
 		}
 		return false
 	}
-	mut code, _ := zftp.read()?
+	mut code, _ := zftp.read()!
 	if code == ftp.logged_in {
 		return true
 	}
@@ -134,7 +134,7 @@ pub fn (mut zftp FTP) login(user string, passwd string) ?bool {
 		}
 		return false
 	}
-	code, _ = zftp.read()?
+	code, _ = zftp.read()!
 	if code == ftp.logged_in {
 		return true
 	}
@@ -142,15 +142,15 @@ pub fn (mut zftp FTP) login(user string, passwd string) ?bool {
 }
 
 // close closes the FTP connection.
-pub fn (mut zftp FTP) close() ? {
-	zftp.write('QUIT')?
-	zftp.conn.close()?
+pub fn (mut zftp FTP) close() ! {
+	zftp.write('QUIT')!
+	zftp.conn.close()!
 }
 
 // pwd returns the current working directory on the remote host for the logged in user.
-pub fn (mut zftp FTP) pwd() ?string {
-	zftp.write('PWD')?
-	_, data := zftp.read()?
+pub fn (mut zftp FTP) pwd() !string {
+	zftp.write('PWD')!
+	_, data := zftp.read()!
 	spl := data.split('"') // "
 	if spl.len >= 2 {
 		return spl[1]
@@ -159,9 +159,9 @@ pub fn (mut zftp FTP) pwd() ?string {
 }
 
 // cd changes the current working directory to the specified remote directory `dir`.
-pub fn (mut zftp FTP) cd(dir string) ? {
+pub fn (mut zftp FTP) cd(dir string) ! {
 	zftp.write('CWD $dir') or { return }
-	mut code, mut data := zftp.read()?
+	mut code, mut data := zftp.read()!
 	match int(code) {
 		ftp.denied {
 			$if debug {
@@ -169,7 +169,7 @@ pub fn (mut zftp FTP) cd(dir string) ? {
 			}
 		}
 		ftp.complete {
-			code, data = zftp.read()?
+			code, data = zftp.read()!
 		}
 		else {}
 	}
@@ -178,7 +178,7 @@ pub fn (mut zftp FTP) cd(dir string) ? {
 	}
 }
 
-fn new_dtp(msg string) ?&DTP {
+fn new_dtp(msg string) !&DTP {
 	if !is_dtp_message_valid(msg) {
 		return error('Bad message')
 	}
@@ -194,32 +194,32 @@ fn new_dtp(msg string) ?&DTP {
 	return dtp
 }
 
-fn (mut zftp FTP) pasv() ?&DTP {
-	zftp.write('PASV')?
-	code, data := zftp.read()?
+fn (mut zftp FTP) pasv() !&DTP {
+	zftp.write('PASV')!
+	code, data := zftp.read()!
 	$if debug {
 		println('pass: $data')
 	}
 	if code != ftp.passive_mode {
 		return error('pasive mode not allowed')
 	}
-	dtp := new_dtp(data)?
+	dtp := new_dtp(data)!
 	return dtp
 }
 
 // dir returns a list of the files in the current working directory.
-pub fn (mut zftp FTP) dir() ?[]string {
+pub fn (mut zftp FTP) dir() ![]string {
 	mut dtp := zftp.pasv() or { return error('Cannot establish data connection') }
-	zftp.write('LIST')?
-	code, _ := zftp.read()?
+	zftp.write('LIST')!
+	code, _ := zftp.read()!
 	if code == ftp.denied {
 		return error('`LIST` denied')
 	}
 	if code != ftp.open_data_connection {
 		return error('Data channel empty')
 	}
-	list_dir := dtp.read()?
-	result, _ := zftp.read()?
+	list_dir := dtp.read()!
+	result, _ := zftp.read()!
 	if result != ftp.close_data_connection {
 		println('`LIST` not ok')
 	}
@@ -235,17 +235,17 @@ pub fn (mut zftp FTP) dir() ?[]string {
 }
 
 // get retrieves `file` from the remote host.
-pub fn (mut zftp FTP) get(file string) ?[]u8 {
+pub fn (mut zftp FTP) get(file string) ![]u8 {
 	mut dtp := zftp.pasv() or { return error('Cannot stablish data connection') }
-	zftp.write('RETR $file')?
-	code, _ := zftp.read()?
+	zftp.write('RETR $file')!
+	code, _ := zftp.read()!
 	if code == ftp.denied {
 		return error('Permission denied')
 	}
 	if code != ftp.open_data_connection {
 		return error('Data connection not ready')
 	}
-	blob := dtp.read()?
+	blob := dtp.read()!
 	dtp.close()
 	return blob
 }

vlib/net/ftp/ftp_test.v

@@ -11,17 +11,17 @@ fn test_ftp_cleint() {
 	ftp_client_test_inside() or { panic(err) }
 }
 
-fn ftp_client_test_inside() ? {
+fn ftp_client_test_inside() ! {
 	mut zftp := ftp.new()
 	// eprintln(zftp)
 	defer {
 		zftp.close() or { panic(err) }
 	}
-	connect_result := zftp.connect('ftp.redhat.com')?
+	connect_result := zftp.connect('ftp.redhat.com')!
 	assert connect_result
-	login_result := zftp.login('ftp', 'ftp')?
+	login_result := zftp.login('ftp', 'ftp')!
 	assert login_result
-	pwd := zftp.pwd()?
+	pwd := zftp.pwd()!
 	assert pwd.len > 0
 	zftp.cd('/') or {
 		assert false

vlib/net/http/backend_nix.c.v

@@ -6,14 +6,14 @@ module http
 import net.ssl
 import strings
 
-fn (req &Request) ssl_do(port int, method Method, host_name string, path string) ?Response {
+fn (req &Request) ssl_do(port int, method Method, host_name string, path string) !Response {
 	mut ssl_conn := ssl.new_ssl_conn(
 		verify: req.verify
 		cert: req.cert
 		cert_key: req.cert_key
 		validate: req.validate
 		in_memory_verification: req.in_memory_verification
-	)?
+	)!
 	ssl_conn.dial(host_name, port) or { return err }
 
 	req_headers := req.build_request_headers(method, host_name, path)
@@ -38,7 +38,7 @@ fn (req &Request) ssl_do(port int, method Method, host_name string, path string)
 		}
 		unsafe { content.write_ptr(bp, len) }
 	}
-	ssl_conn.shutdown()?
+	ssl_conn.shutdown()!
 	response_text := content.str()
 	$if trace_http_response ? {
 		eprintln('< $response_text')

vlib/net/http/backend_windows.c.v

@@ -13,7 +13,7 @@ $if gcboehm ? {
 
 fn C.new_tls_context() C.TlsContext
 
-fn (req &Request) ssl_do(port int, method Method, host_name string, path string) ?Response {
+fn (req &Request) ssl_do(port int, method Method, host_name string, path string) !Response {
 	mut ctx := C.new_tls_context()
 	C.vschannel_init(&ctx)
 	mut buff := unsafe { malloc_noscan(C.vsc_init_resp_buff_size) }

vlib/net/http/cookie.v

@@ -294,7 +294,7 @@ pub fn is_cookie_domain_name(_s string) bool {
 	return ok
 }
 
-fn parse_cookie_value(_raw string, allow_double_quote bool) ?string {
+fn parse_cookie_value(_raw string, allow_double_quote bool) !string {
 	mut raw := _raw
 	// Strip the quotes, if present
 	if allow_double_quote && raw.len > 1 && raw[0] == `"` && raw[raw.len - 1] == `"` {
@@ -320,7 +320,7 @@ fn is_cookie_name_valid(name string) bool {
 	return true
 }
 
-fn parse_cookie(line string) ?Cookie {
+fn parse_cookie(line string) !Cookie {
 	mut parts := line.trim_space().split(';')
 	if parts.len == 1 && parts[0] == '' {
 		return error('malformed cookie')

vlib/net/http/download.v

@@ -7,7 +7,7 @@ import os
 
 // download_file retrieves a document from the URL `url`,
 // and saves it in the output file path `out_file_path`.
-pub fn download_file(url string, out_file_path string) ? {
+pub fn download_file(url string, out_file_path string) ! {
 	$if debug_http ? {
 		println('http.download_file url=$url out_file_path=$out_file_path')
 	}
@@ -18,7 +18,7 @@ pub fn download_file(url string, out_file_path string) ? {
 	$if debug_http ? {
 		println('http.download_file saving $s.body.len bytes')
 	}
-	os.write_file(out_file_path, s.body)?
+	os.write_file(out_file_path, s.body)!
 }
 
 // TODO: implement download_file_with_progress

vlib/net/http/header.v

@@ -363,9 +363,9 @@ pub fn new_header_from_map(kvs map[CommonHeader]string) Header {
 }
 
 // new_custom_header_from_map creates a Header from string key value pairs
-pub fn new_custom_header_from_map(kvs map[string]string) ?Header {
+pub fn new_custom_header_from_map(kvs map[string]string) !Header {
 	mut h := new_header()
-	h.add_custom_map(kvs)?
+	h.add_custom_map(kvs)!
 	return h
 }
 
@@ -378,8 +378,8 @@ pub fn (mut h Header) add(key CommonHeader, value string) {
 
 // add_custom appends a value to a custom header key. This function will
 // return an error if the key contains invalid header characters.
-pub fn (mut h Header) add_custom(key string, value string) ? {
-	is_valid(key)?
+pub fn (mut h Header) add_custom(key string, value string) ! {
+	is_valid(key)!
 	h.data[key] << value
 	h.add_key(key)
 }
@@ -392,9 +392,9 @@ pub fn (mut h Header) add_map(kvs map[CommonHeader]string) {
 }
 
 // add_custom_map appends the value for each custom header key.
-pub fn (mut h Header) add_custom_map(kvs map[string]string) ? {
+pub fn (mut h Header) add_custom_map(kvs map[string]string) ! {
 	for k, v in kvs {
-		h.add_custom(k, v)?
+		h.add_custom(k, v)!
 	}
 }
 
@@ -410,8 +410,8 @@ pub fn (mut h Header) set(key CommonHeader, value string) {
 // function will clear any other values that exist for the header. This
 // function will return an error if the key contains invalid header
 // characters.
-pub fn (mut h Header) set_custom(key string, value string) ? {
-	is_valid(key)?
+pub fn (mut h Header) set_custom(key string, value string) ! {
+	is_valid(key)!
 	h.data[key] = [value]
 	h.add_key(key)
 }
@@ -479,37 +479,37 @@ pub fn (h Header) contains_custom(key string, flags HeaderQueryConfig) bool {
 
 // get gets the first value for the CommonHeader, or none if the key
 // does not exist.
-pub fn (h Header) get(key CommonHeader) ?string {
+pub fn (h Header) get(key CommonHeader) !string {
 	return h.get_custom(key.str())
 }
 
 // get_custom gets the first value for the custom header, or none if
 // the key does not exist.
-pub fn (h Header) get_custom(key string, flags HeaderQueryConfig) ?string {
+pub fn (h Header) get_custom(key string, flags HeaderQueryConfig) !string {
 	mut data_key := key
 	if !flags.exact {
 		// get the first key from key metadata
 		k := key.to_lower()
 		if h.keys[k].len == 0 {
-			return none
+			return error('none')
 		}
 		data_key = h.keys[k][0]
 	}
 	if h.data[data_key].len == 0 {
-		return none
+		return error('none')
 	}
 	return h.data[data_key][0]
 }
 
 // starting_with gets the first header starting with key, or none if
 // the key does not exist.
-pub fn (h Header) starting_with(key string) ?string {
+pub fn (h Header) starting_with(key string) !string {
 	for k, _ in h.data {
 		if k.starts_with(key) {
 			return k
 		}
 	}
-	return none
+	return error('none')
 }
 
 // values gets all values for the CommonHeader.
@@ -642,7 +642,7 @@ pub fn (err HeaderKeyError) code() int {
 }
 
 // is_valid checks if the header token contains all valid bytes
-fn is_valid(header string) ? {
+fn is_valid(header string) ! {
 	for _, c in header {
 		if int(c) >= 128 || !is_token(c) {
 			return IError(HeaderKeyError{
@@ -676,7 +676,7 @@ pub fn (h Header) str() string {
 }
 
 // parse_headers parses a newline delimited string into a Header struct
-fn parse_headers(s string) ?Header {
+fn parse_headers(s string) !Header {
 	mut h := new_header()
 	mut last_key := ''
 	mut last_value := ''
@@ -689,15 +689,15 @@ fn parse_headers(s string) ?Header {
 			last_value += ' ${line.trim(' \t')}'
 			continue
 		} else if last_key != '' {
-			h.add_custom(last_key, last_value)?
+			h.add_custom(last_key, last_value)!
 		}
-		last_key, last_value = parse_header(line)?
+		last_key, last_value = parse_header(line)!
 	}
-	h.add_custom(last_key, last_value)?
+	h.add_custom(last_key, last_value)!
 	return h
 }
 
-fn parse_header(s string) ?(string, string) {
+fn parse_header(s string) !(string, string) {
 	if !s.contains(':') {
 		return error('missing colon in header')
 	}

vlib/net/http/http.v

@@ -31,7 +31,7 @@ pub mut:
 	allow_redirect         bool = true // whether to allow redirect
 }
 
-pub fn new_request(method Method, url_ string, data string) ?Request {
+pub fn new_request(method Method, url_ string, data string) !Request {
 	url := if method == .get && !url_.contains('?') { url_ + '?' + data } else { url_ }
 	// println('new req() method=$method url="$url" dta="$data"')
 	return Request{
@@ -47,12 +47,12 @@ pub fn new_request(method Method, url_ string, data string) ?Request {
 }
 
 // get sends a GET HTTP request to the URL
-pub fn get(url string) ?Response {
+pub fn get(url string) !Response {
 	return fetch(method: .get, url: url)
 }
 
 // post sends a POST HTTP request to the URL with a string data
-pub fn post(url string, data string) ?Response {
+pub fn post(url string, data string) !Response {
 	return fetch(
 		method: .post
 		url: url
@@ -62,7 +62,7 @@ pub fn post(url string, data string) ?Response {
 }
 
 // post_json sends a POST HTTP request to the URL with a JSON data
-pub fn post_json(url string, data string) ?Response {
+pub fn post_json(url string, data string) !Response {
 	return fetch(
 		method: .post
 		url: url
@@ -72,7 +72,7 @@ pub fn post_json(url string, data string) ?Response {
 }
 
 // post_form sends a POST HTTP request to the URL with X-WWW-FORM-URLENCODED data
-pub fn post_form(url string, data map[string]string) ?Response {
+pub fn post_form(url string, data map[string]string) !Response {
 	return fetch(
 		method: .post
 		url: url
@@ -90,7 +90,7 @@ pub mut:
 }
 
 // post_multipart_form sends a POST HTTP request to the URL with multipart form data
-pub fn post_multipart_form(url string, conf PostMultipartFormConfig) ?Response {
+pub fn post_multipart_form(url string, conf PostMultipartFormConfig) !Response {
 	body, boundary := multipart_form_body(conf.form, conf.files)
 	mut header := conf.header
 	header.set(.content_type, 'multipart/form-data; boundary="$boundary"')
@@ -103,7 +103,7 @@ pub fn post_multipart_form(url string, conf PostMultipartFormConfig) ?Response {
 }
 
 // put sends a PUT HTTP request to the URL with a string data
-pub fn put(url string, data string) ?Response {
+pub fn put(url string, data string) !Response {
 	return fetch(
 		method: .put
 		url: url
@@ -113,7 +113,7 @@ pub fn put(url string, data string) ?Response {
 }
 
 // patch sends a PATCH HTTP request to the URL with a string data
-pub fn patch(url string, data string) ?Response {
+pub fn patch(url string, data string) !Response {
 	return fetch(
 		method: .patch
 		url: url
@@ -123,17 +123,17 @@ pub fn patch(url string, data string) ?Response {
 }
 
 // head sends a HEAD HTTP request to the URL
-pub fn head(url string) ?Response {
+pub fn head(url string) !Response {
 	return fetch(method: .head, url: url)
 }
 
 // delete sends a DELETE HTTP request to the URL
-pub fn delete(url string) ?Response {
+pub fn delete(url string) !Response {
 	return fetch(method: .delete, url: url)
 }
 
 // fetch sends an HTTP request to the URL with the given method and configurations
-pub fn fetch(config FetchConfig) ?Response {
+pub fn fetch(config FetchConfig) !Response {
 	if config.url == '' {
 		return error('http.fetch: empty url')
 	}
@@ -154,7 +154,7 @@ pub fn fetch(config FetchConfig) ?Response {
 		in_memory_verification: config.in_memory_verification
 		allow_redirect: config.allow_redirect
 	}
-	res := req.do()?
+	res := req.do()!
 	return res
 }
 
@@ -176,14 +176,14 @@ pub fn url_encode_form_data(data map[string]string) string {
 }
 
 [deprecated: 'use fetch()']
-fn fetch_with_method(method Method, _config FetchConfig) ?Response {
+fn fetch_with_method(method Method, _config FetchConfig) !Response {
 	mut config := _config
 	config.method = method
 	return fetch(config)
 }
 
-fn build_url_from_fetch(config FetchConfig) ?string {
-	mut url := urllib.parse(config.url)?
+fn build_url_from_fetch(config FetchConfig) !string {
+	mut url := urllib.parse(config.url)!
 	if config.params.len == 0 {
 		return url.str()
 	}

vlib/net/http/http_httpbin_test.v

@@ -14,7 +14,7 @@ struct HttpbinResponseBody {
 	url     string
 }
 
-fn http_fetch_mock(_methods []string, _config FetchConfig) ?[]Response {
+fn http_fetch_mock(_methods []string, _config FetchConfig) ![]Response {
 	url := 'https://httpbin.org/'
 	methods := if _methods.len == 0 { ['GET', 'POST', 'PATCH', 'PUT', 'DELETE'] } else { _methods }
 	mut config := _config
@@ -23,7 +23,7 @@ fn http_fetch_mock(_methods []string, _config FetchConfig) ?[]Response {
 	for method in methods {
 		lmethod := method.to_lower()
 		config.method = method_from_str(method)
-		res := fetch(FetchConfig{ ...config, url: url + lmethod })?
+		res := fetch(FetchConfig{ ...config, url: url + lmethod })!
 		// TODO
 		// body := json.decode(HttpbinResponseBody,res.body)?
 		result << res
@@ -75,12 +75,12 @@ fn test_http_fetch_with_params() {
 	}
 }
 
-fn test_http_fetch_with_headers() ? {
+fn test_http_fetch_with_headers() ! {
 	$if !network ? {
 		return
 	}
 	mut header := new_header()
-	header.add_custom('Test-Header', 'hello world')?
+	header.add_custom('Test-Header', 'hello world')!
 	responses := http_fetch_mock([],
 		header: header
 	) or { panic(err) }

vlib/net/http/request.v

@@ -48,12 +48,12 @@ pub fn (mut req Request) add_header(key CommonHeader, val string) {
 
 // add_custom_header adds the key and value of an HTTP request header
 // This method may fail if the key contains characters that are not permitted
-pub fn (mut req Request) add_custom_header(key string, val string) ? {
+pub fn (mut req Request) add_custom_header(key string, val string) ! {
 	return req.header.add_custom(key, val)
 }
 
 // do will send the HTTP request and returns `http.Response` as soon as the response is recevied
-pub fn (req &Request) do() ?Response {
+pub fn (req &Request) do() !Response {
 	mut url := urllib.parse(req.url) or { return error('http.Request.do: invalid url $req.url') }
 	mut rurl := url
 	mut resp := Response{}
@@ -62,7 +62,7 @@ pub fn (req &Request) do() ?Response {
 		if no_redirects == max_redirects {
 			return error('http.request.do: maximum number of redirects reached ($max_redirects)')
 		}
-		qresp := req.method_and_url_to_response(req.method, rurl)?
+		qresp := req.method_and_url_to_response(req.method, rurl)!
 		resp = qresp
 		if !req.allow_redirect {
 			break
@@ -88,7 +88,7 @@ pub fn (req &Request) do() ?Response {
 	return resp
 }
 
-fn (req &Request) method_and_url_to_response(method Method, url urllib.URL) ?Response {
+fn (req &Request) method_and_url_to_response(method Method, url urllib.URL) !Response {
 	host_name := url.hostname()
 	scheme := url.scheme
 	p := url.escaped_path().trim_left('/')
@@ -105,11 +105,11 @@ fn (req &Request) method_and_url_to_response(method Method, url urllib.URL) ?Res
 	// println('fetch $method, $scheme, $host_name, $nport, $path ')
 	if scheme == 'https' {
 		// println('ssl_do( $nport, $method, $host_name, $path )')
-		res := req.ssl_do(nport, method, host_name, path)?
+		res := req.ssl_do(nport, method, host_name, path)!
 		return res
 	} else if scheme == 'http' {
 		// println('http_do( $nport, $method, $host_name, $path )')
-		res := req.http_do('$host_name:$nport', method, path)?
+		res := req.http_do('$host_name:$nport', method, path)!
 		return res
 	}
 	return error('http.request.method_and_url_to_response: unsupported scheme: "$scheme"')
@@ -151,19 +151,19 @@ fn (req &Request) build_request_cookies_header() string {
 	return 'Cookie: ' + cookie.join('; ') + '\r\n'
 }
 
-fn (req &Request) http_do(host string, method Method, path string) ?Response {
-	host_name, _ := net.split_address(host)?
+fn (req &Request) http_do(host string, method Method, path string) !Response {
+	host_name, _ := net.split_address(host)!
 	s := req.build_request_headers(method, host_name, path)
-	mut client := net.dial_tcp(host)?
+	mut client := net.dial_tcp(host)!
 	client.set_read_timeout(req.read_timeout)
 	client.set_write_timeout(req.write_timeout)
 	// TODO this really needs to be exposed somehow
-	client.write(s.bytes())?
+	client.write(s.bytes())!
 	$if trace_http_request ? {
 		eprintln('> $s')
 	}
-	mut bytes := io.read_all(reader: client)?
-	client.close()?
+	mut bytes := io.read_all(reader: client)!
+	client.close()!
 	response_text := bytes.bytestr()
 	$if trace_http_response ? {
 		eprintln('< $response_text')
@@ -178,8 +178,8 @@ pub fn (req &Request) referer() string {
 
 // parse_request parses a raw HTTP request into a Request object.
 // See also: `parse_request_head`, which parses only the headers.
-pub fn parse_request(mut reader io.BufferedReader) ?Request {
-	mut request := parse_request_head(mut reader)?
+pub fn parse_request(mut reader io.BufferedReader) !Request {
+	mut request := parse_request_head(mut reader)!
 
 	// body
 	mut body := []u8{}
@@ -199,18 +199,18 @@ pub fn parse_request(mut reader io.BufferedReader) ?Request {
 }
 
 // parse_request_head parses *only* the header of a raw HTTP request into a Request object
-pub fn parse_request_head(mut reader io.BufferedReader) ?Request {
+pub fn parse_request_head(mut reader io.BufferedReader) !Request {
 	// request line
-	mut line := reader.read_line()?
-	method, target, version := parse_request_line(line)?
+	mut line := reader.read_line()!
+	method, target, version := parse_request_line(line)!
 
 	// headers
 	mut header := new_header()
-	line = reader.read_line()?
+	line = reader.read_line()!
 	for line != '' {
-		key, value := parse_header(line)?
-		header.add_custom(key, value)?
-		line = reader.read_line()?
+		key, value := parse_header(line)!
+		header.add_custom(key, value)!
+		line = reader.read_line()!
 	}
 	header.coerce(canonicalize: true)
 
@@ -228,13 +228,13 @@ pub fn parse_request_head(mut reader io.BufferedReader) ?Request {
 	}
 }
 
-fn parse_request_line(s string) ?(Method, urllib.URL, Version) {
+fn parse_request_line(s string) !(Method, urllib.URL, Version) {
 	words := s.split(' ')
 	if words.len != 3 {
 		return error('malformed request line')
 	}
 	method := method_from_str(words[0])
-	target := urllib.parse(words[1])?
+	target := urllib.parse(words[1])!
 	version := version_from_str(words[2])
 	if version == .unknown {
 		return error('unsupported version')

vlib/net/http/request_test.v

@@ -178,7 +178,7 @@ fn test_parse_large_body() {
 	body := 'A'.repeat(101) // greater than max_bytes
 	req := 'GET / HTTP/1.1\r\nContent-Length: $body.len\r\n\r\n$body'
 	mut reader_ := reader(req)
-	result := parse_request(mut reader_)?
+	result := parse_request(mut reader_)!
 	assert result.data.len == body.len
 	assert result.data == body
 }

vlib/net/http/response.v

@@ -35,11 +35,11 @@ pub fn (resp Response) bytestr() string {
 }
 
 // Parse a raw HTTP response into a Response object
-pub fn parse_response(resp string) ?Response {
-	version, status_code, status_msg := parse_status_line(resp.all_before('\n'))?
+pub fn parse_response(resp string) !Response {
+	version, status_code, status_msg := parse_status_line(resp.all_before('\n'))!
 	// Build resp header map and separate the body
-	start_idx, end_idx := find_headers_range(resp)?
-	header := parse_headers(resp.substr(start_idx, end_idx))?
+	start_idx, end_idx := find_headers_range(resp)!
+	header := parse_headers(resp.substr(start_idx, end_idx))!
 	mut body := resp.substr(end_idx, resp.len)
 	if header.get(.transfer_encoding) or { '' } == 'chunked' {
 		body = chunked.decode(body)
@@ -56,7 +56,7 @@ pub fn parse_response(resp string) ?Response {
 
 // parse_status_line parses the first HTTP response line into the HTTP
 // version, status code, and reason phrase
-fn parse_status_line(line string) ?(string, int, string) {
+fn parse_status_line(line string) !(string, int, string) {
 	if line.len < 5 || line[..5].to_lower() != 'http/' {
 		return error('response does not start with HTTP/')
 	}
@@ -73,7 +73,7 @@ fn parse_status_line(line string) ?(string, int, string) {
 	for digit in digits {
 		strconv.atoi(digit) or { return error('HTTP version must contain only integers') }
 	}
-	return version, strconv.atoi(data[1])?, data[2]
+	return version, strconv.atoi(data[1])!, data[2]
 }
 
 // cookies parses the Set-Cookie headers into Cookie objects
@@ -138,7 +138,7 @@ pub fn new_response(conf ResponseConfig) Response {
 // index of the headers in the string, including the trailing newlines. This
 // helper function expects the first line in `data` to be the HTTP status line
 // (HTTP/1.1 200 OK).
-fn find_headers_range(data string) ?(int, int) {
+fn find_headers_range(data string) !(int, int) {
 	start_idx := data.index('\n') or { return error('no start index found') } + 1
 	mut count := 0
 	for i := start_idx; i < data.len; i++ {

vlib/net/http/response_test.v

@@ -26,7 +26,7 @@ fn test_response_bytestr() {
 // check_headers is a helper function for asserting all expected headers
 // are found because rendered header order is not guaranteed. The check
 // is O(n^2) which is fine for small lists.
-fn check_headers(expected []string, found []string) ? {
+fn check_headers(expected []string, found []string) ! {
 	assert expected.len == found.len
 	for header in expected {
 		if !found.contains(header) {

vlib/net/http/server.v

@@ -34,11 +34,14 @@ pub mut:
 	accept_timeout time.Duration = 30 * time.second
 }
 
-pub fn (mut s Server) listen_and_serve() ? {
+pub fn (mut s Server) listen_and_serve() {
 	if s.handler is DebugHandler {
 		eprintln('Server handler not set, using debug handler')
 	}
-	s.listener = net.listen_tcp(.ip6, ':$s.port')?
+	s.listener = net.listen_tcp(.ip6, ':$s.port') or {
+		eprintln('Listening on :$s.port failed')
+		return
+	}
 	s.listener.set_accept_timeout(s.accept_timeout)
 	eprintln('Listening on :$s.port')
 	s.state = .running

vlib/net/http/server_test.v

@@ -11,7 +11,7 @@ fn test_server_stop() {
 	server.stop()
 	assert server.status() == .stopped
 	assert watch.elapsed() < 100 * time.millisecond
-	t.wait()?
+	t.wait()
 	assert watch.elapsed() < 999 * time.millisecond
 }
 
@@ -26,7 +26,7 @@ fn test_server_close() {
 	server.close()
 	assert server.status() == .closed
 	assert watch.elapsed() < 100 * time.millisecond
-	t.wait()?
+	t.wait()
 	assert watch.elapsed() < 999 * time.millisecond
 }
 
@@ -71,19 +71,19 @@ fn test_server_custom_handler() {
 	for server.status() != .running {
 		time.sleep(10 * time.millisecond)
 	}
-	x := http.fetch(url: 'http://localhost:$cport/endpoint?abc=xyz', data: 'my data')?
+	x := http.fetch(url: 'http://localhost:$cport/endpoint?abc=xyz', data: 'my data')!
 	assert x.body == 'my data, /endpoint?abc=xyz'
 	assert x.status_code == 200
 	assert x.http_version == '1.1'
-	y := http.fetch(url: 'http://localhost:$cport/another/endpoint', data: 'abcde')?
+	y := http.fetch(url: 'http://localhost:$cport/another/endpoint', data: 'abcde')!
 	assert y.body == 'abcde, /another/endpoint'
 	assert y.status_code == 200
 	assert y.status() == .ok
 	assert y.http_version == '1.1'
 	//
-	http.fetch(url: 'http://localhost:$cport/something/else')?
+	http.fetch(url: 'http://localhost:$cport/something/else')!
 	server.stop()
-	t.wait()?
+	t.wait()
 	assert handler.counter == 3
 	assert handler.oks == 2
 	assert handler.not_founds == 1

vlib/net/mbedtls/ssl_connection.v

@@ -52,7 +52,7 @@ pub struct SSLConnectConfig {
 }
 
 // new_ssl_conn returns a new SSLConn with the given config.
-pub fn new_ssl_conn(config SSLConnectConfig) ?&SSLConn {
+pub fn new_ssl_conn(config SSLConnectConfig) !&SSLConn {
 	mut conn := &SSLConn{
 		config: config
 	}
@@ -68,7 +68,7 @@ enum Select {
 }
 
 // shutdown terminates the ssl connection and does cleanup
-pub fn (mut s SSLConn) shutdown() ? {
+pub fn (mut s SSLConn) shutdown() ! {
 	if !s.opened {
 		return error('ssl connection not open')
 	}
@@ -82,16 +82,16 @@ pub fn (mut s SSLConn) shutdown() ? {
 	if s.owns_socket {
 		$if windows {
 			C.shutdown(s.handle, C.SD_BOTH)
-			net.socket_error(C.closesocket(s.handle))?
+			net.socket_error(C.closesocket(s.handle))!
 		} $else {
 			C.shutdown(s.handle, C.SHUT_RDWR)
-			net.socket_error(C.close(s.handle))?
+			net.socket_error(C.close(s.handle))!
 		}
 	}
 }
 
 // connect to server using mbedtls
-fn (mut s SSLConn) init() ? {
+fn (mut s SSLConn) init() ! {
 	C.mbedtls_net_init(&s.server_fd)
 	C.mbedtls_ssl_init(&s.ssl)
 	C.mbedtls_ssl_config_init(&s.conf)
@@ -157,7 +157,7 @@ fn (mut s SSLConn) init() ? {
 }
 
 // connect sets up an ssl connection on an existing TCP connection
-pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ? {
+pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ! {
 	if s.opened {
 		return error('ssl connection already open')
 	}
@@ -183,7 +183,7 @@ pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ? {
 }
 
 // dial opens an ssl connection on hostname:port
-pub fn (mut s SSLConn) dial(hostname string, port int) ? {
+pub fn (mut s SSLConn) dial(hostname string, port int) ! {
 	s.owns_socket = true
 	if s.opened {
 		return error('ssl connection already open')
@@ -216,7 +216,7 @@ pub fn (mut s SSLConn) dial(hostname string, port int) ? {
 }
 
 // socket_read_into_ptr reads `len` bytes into `buf`
-pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) ?int {
+pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) !int {
 	mut res := 0
 	for {
 		res = C.mbedtls_ssl_read(&s.ssl, buf_ptr, len)
@@ -227,13 +227,13 @@ pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) ?int {
 		} else {
 			match res {
 				C.MBEDTLS_ERR_SSL_WANT_READ {
-					ready := @select(s.handle, .read, s.duration)?
+					ready := @select(s.handle, .read, s.duration)!
 					if !ready {
 						return net.err_timed_out
 					}
 				}
 				C.MBEDTLS_ERR_SSL_WANT_WRITE {
-					ready := @select(s.handle, .write, s.duration)?
+					ready := @select(s.handle, .write, s.duration)!
 					if !ready {
 						return net.err_timed_out
 					}
@@ -257,7 +257,7 @@ pub fn (mut s SSLConn) read(mut buffer []u8) !int {
 }
 
 // write_ptr writes `len` bytes from `bytes` to the ssl connection
-pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
+pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) !int {
 	unsafe {
 		mut ptr_base := bytes
 		mut total_sent := 0
@@ -269,7 +269,7 @@ pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
 				match sent {
 					C.MBEDTLS_ERR_SSL_WANT_READ {
 						for {
-							ready := @select(s.handle, .read, s.duration)?
+							ready := @select(s.handle, .read, s.duration)!
 							if ready {
 								break
 							}
@@ -278,7 +278,7 @@ pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
 					}
 					C.MBEDTLS_ERR_SSL_WANT_WRITE {
 						for {
-							ready := @select(s.handle, .write, s.duration)?
+							ready := @select(s.handle, .write, s.duration)!
 							if ready {
 								break
 							}
@@ -297,12 +297,12 @@ pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
 }
 
 // write writes data from `bytes` to the ssl connection
-pub fn (mut s SSLConn) write(bytes []u8) ?int {
+pub fn (mut s SSLConn) write(bytes []u8) !int {
 	return s.write_ptr(&u8(bytes.data), bytes.len)
 }
 
 // write_string writes a string to the ssl connection
-pub fn (mut s SSLConn) write_string(str string) ?int {
+pub fn (mut s SSLConn) write_string(str string) !int {
 	return s.write_ptr(str.str, str.len)
 }
 
@@ -313,7 +313,7 @@ This is basically a copy of Emily socket implementation of select.
 */
 
 // Select waits for an io operation (specified by parameter `test`) to be available
-fn @select(handle int, test Select, timeout time.Duration) ?bool {
+fn @select(handle int, test Select, timeout time.Duration) !bool {
 	set := C.fd_set{}
 
 	C.FD_ZERO(&set)
@@ -336,13 +336,13 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 
 	match test {
 		.read {
-			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))!
 		}
 		.write {
-			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))!
 		}
 		.except {
-			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))!
 		}
 	}
 

vlib/net/openssl/openssl.v

@@ -1,7 +1,7 @@
 module openssl
 
 // ssl_error returns non error ssl code or error if unrecoverable and we should panic
-fn ssl_error(ret int, ssl voidptr) ?SSLError {
+fn ssl_error(ret int, ssl voidptr) !SSLError {
 	res := C.SSL_get_error(ssl, ret)
 	match unsafe { SSLError(res) } {
 		.ssl_error_syscall {

vlib/net/openssl/ssl_connection.v

@@ -28,7 +28,7 @@ pub struct SSLConnectConfig {
 }
 
 // new_ssl_conn instance an new SSLCon struct
-pub fn new_ssl_conn(config SSLConnectConfig) ?&SSLConn {
+pub fn new_ssl_conn(config SSLConnectConfig) !&SSLConn {
 	mut conn := &SSLConn{
 		config: config
 		sslctx: 0
@@ -47,7 +47,7 @@ enum Select {
 }
 
 // shutdown closes the ssl connection and does cleanup
-pub fn (mut s SSLConn) shutdown() ? {
+pub fn (mut s SSLConn) shutdown() ! {
 	if s.ssl != 0 {
 		mut res := 0
 		for {
@@ -100,15 +100,15 @@ pub fn (mut s SSLConn) shutdown() ? {
 	if s.owns_socket {
 		$if windows {
 			C.shutdown(s.handle, C.SD_BOTH)
-			net.socket_error(C.closesocket(s.handle))?
+			net.socket_error(C.closesocket(s.handle))!
 		} $else {
 			C.shutdown(s.handle, C.SHUT_RDWR)
-			net.socket_error(C.close(s.handle))?
+			net.socket_error(C.close(s.handle))!
 		}
 	}
 }
 
-fn (mut s SSLConn) init() ? {
+fn (mut s SSLConn) init() ! {
 	s.sslctx = unsafe { C.SSL_CTX_new(C.SSLv23_client_method()) }
 	if s.sslctx == 0 {
 		return error("Couldn't get ssl context")
@@ -136,13 +136,13 @@ fn (mut s SSLConn) init() ? {
 			cert = os.temp_dir() + '/v_cert' + now
 			cert_key = os.temp_dir() + '/v_cert_key' + now
 			if s.config.verify != '' {
-				os.write_file(verify, s.config.verify)?
+				os.write_file(verify, s.config.verify)!
 			}
 			if s.config.cert != '' {
-				os.write_file(cert, s.config.cert)?
+				os.write_file(cert, s.config.cert)!
 			}
 			if s.config.cert_key != '' {
-				os.write_file(cert_key, s.config.cert_key)?
+				os.write_file(cert_key, s.config.cert_key)!
 			}
 		}
 		if s.config.verify != '' {
@@ -175,7 +175,7 @@ fn (mut s SSLConn) init() ? {
 }
 
 // connect to server using OpenSSL
-pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ? {
+pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ! {
 	s.handle = tcp_conn.sock.handle
 	s.duration = tcp_conn.read_timeout()
 
@@ -192,7 +192,7 @@ pub fn (mut s SSLConn) connect(mut tcp_conn net.TcpConn, hostname string) ? {
 }
 
 // dial opens an ssl connection on hostname:port
-pub fn (mut s SSLConn) dial(hostname string, port int) ? {
+pub fn (mut s SSLConn) dial(hostname string, port int) ! {
 	s.owns_socket = true
 	mut tcp_conn := net.dial_tcp('$hostname:$port') or { return err }
 	$if macos {
@@ -201,14 +201,14 @@ pub fn (mut s SSLConn) dial(hostname string, port int) ? {
 	s.connect(mut tcp_conn, hostname) or { return err }
 }
 
-fn (mut s SSLConn) complete_connect() ? {
+fn (mut s SSLConn) complete_connect() ! {
 	for {
 		mut res := C.SSL_connect(voidptr(s.ssl))
 		if res != 1 {
-			err_res := ssl_error(res, s.ssl)?
+			err_res := ssl_error(res, s.ssl)!
 			if err_res == .ssl_error_want_read {
 				for {
-					ready := @select(s.handle, .read, s.duration)?
+					ready := @select(s.handle, .read, s.duration)!
 					if ready {
 						break
 					}
@@ -216,7 +216,7 @@ fn (mut s SSLConn) complete_connect() ? {
 				continue
 			} else if err_res == .ssl_error_want_write {
 				for {
-					ready := @select(s.handle, .write, s.duration)?
+					ready := @select(s.handle, .write, s.duration)!
 					if ready {
 						break
 					}
@@ -232,10 +232,10 @@ fn (mut s SSLConn) complete_connect() ? {
 		for {
 			mut res := C.SSL_do_handshake(voidptr(s.ssl))
 			if res != 1 {
-				err_res := ssl_error(res, s.ssl)?
+				err_res := ssl_error(res, s.ssl)!
 				if err_res == .ssl_error_want_read {
 					for {
-						ready := @select(s.handle, .read, s.duration)?
+						ready := @select(s.handle, .read, s.duration)!
 						if ready {
 							break
 						}
@@ -243,7 +243,7 @@ fn (mut s SSLConn) complete_connect() ? {
 					continue
 				} else if err_res == .ssl_error_want_write {
 					for {
-						ready := @select(s.handle, .write, s.duration)?
+						ready := @select(s.handle, .write, s.duration)!
 						if ready {
 							break
 						}
@@ -267,7 +267,7 @@ fn (mut s SSLConn) complete_connect() ? {
 	}
 }
 
-pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) ?int {
+pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) !int {
 	mut res := 0
 	for {
 		res = C.SSL_read(voidptr(s.ssl), buf_ptr, len)
@@ -276,16 +276,16 @@ pub fn (mut s SSLConn) socket_read_into_ptr(buf_ptr &u8, len int) ?int {
 		} else if res == 0 {
 			return IError(io.Eof{})
 		} else {
-			err_res := ssl_error(res, s.ssl)?
+			err_res := ssl_error(res, s.ssl)!
 			match err_res {
 				.ssl_error_want_read {
-					ready := @select(s.handle, .read, s.duration)?
+					ready := @select(s.handle, .read, s.duration)!
 					if !ready {
 						return net.err_timed_out
 					}
 				}
 				.ssl_error_want_write {
-					ready := @select(s.handle, .write, s.duration)?
+					ready := @select(s.handle, .write, s.duration)!
 					if !ready {
 						return net.err_timed_out
 					}
@@ -308,7 +308,7 @@ pub fn (mut s SSLConn) read(mut buffer []u8) !int {
 }
 
 // write_ptr writes `len` bytes from `bytes` to the ssl connection
-pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
+pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) !int {
 	unsafe {
 		mut ptr_base := bytes
 		mut total_sent := 0
@@ -317,17 +317,17 @@ pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
 			remaining := len - total_sent
 			mut sent := C.SSL_write(voidptr(s.ssl), ptr, remaining)
 			if sent <= 0 {
-				err_res := ssl_error(sent, s.ssl)?
+				err_res := ssl_error(sent, s.ssl)!
 				if err_res == .ssl_error_want_read {
 					for {
-						ready := @select(s.handle, .read, s.duration)?
+						ready := @select(s.handle, .read, s.duration)!
 						if ready {
 							break
 						}
 					}
 				} else if err_res == .ssl_error_want_write {
 					for {
-						ready := @select(s.handle, .write, s.duration)?
+						ready := @select(s.handle, .write, s.duration)!
 						if ready {
 							break
 						}
@@ -345,12 +345,12 @@ pub fn (mut s SSLConn) write_ptr(bytes &u8, len int) ?int {
 }
 
 // write writes data from `bytes` to the ssl connection
-pub fn (mut s SSLConn) write(bytes []u8) ?int {
+pub fn (mut s SSLConn) write(bytes []u8) !int {
 	return s.write_ptr(&u8(bytes.data), bytes.len)
 }
 
 // write_string writes a string to the ssl connection
-pub fn (mut s SSLConn) write_string(str string) ?int {
+pub fn (mut s SSLConn) write_string(str string) !int {
 	return s.write_ptr(str.str, str.len)
 }
 
@@ -364,7 +364,7 @@ This is basically a copy of Emily socket implementation of select.
 // }
 
 // Select waits for an io operation (specified by parameter `test`) to be available
-fn @select(handle int, test Select, timeout time.Duration) ?bool {
+fn @select(handle int, test Select, timeout time.Duration) !bool {
 	set := C.fd_set{}
 
 	C.FD_ZERO(&set)
@@ -387,13 +387,13 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 
 	match test {
 		.read {
-			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))!
 		}
 		.write {
-			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))!
 		}
 		.except {
-			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))!
 		}
 	}
 

vlib/net/smtp/smtp.v

@@ -59,7 +59,7 @@ pub struct Mail {
 }
 
 // new_client returns a new SMTP client and connects to it
-pub fn new_client(config Client) ?&Client {
+pub fn new_client(config Client) !&Client {
 	if config.ssl && config.starttls {
 		return error('Can not use both implicit SSL and STARTTLS')
 	}
@@ -67,12 +67,12 @@ pub fn new_client(config Client) ?&Client {
 	mut c := &Client{
 		...config
 	}
-	c.reconnect()?
+	c.reconnect()!
 	return c
 }
 
 // reconnect reconnects to the SMTP server if the connection was closed
-pub fn (mut c Client) reconnect() ? {
+pub fn (mut c Client) reconnect() ! {
 	if c.is_open {
 		return error('Already connected to server')
 	}
@@ -81,7 +81,7 @@ pub fn (mut c Client) reconnect() ? {
 	c.conn = conn
 
 	if c.ssl {
-		c.connect_ssl()?
+		c.connect_ssl()!
 	} else {
 		c.reader = io.new_buffered_reader(reader: c.conn)
 	}
@@ -98,7 +98,7 @@ pub fn (mut c Client) reconnect() ? {
 }
 
 // send sends an email
-pub fn (mut c Client) send(config Mail) ? {
+pub fn (mut c Client) send(config Mail) ! {
 	if !c.is_open {
 		return error('Disconnected from server')
 	}
@@ -113,20 +113,20 @@ pub fn (mut c Client) send(config Mail) ? {
 }
 
 // quit closes the connection to the server
-pub fn (mut c Client) quit() ? {
-	c.send_str('QUIT\r\n')?
-	c.expect_reply(.close)?
+pub fn (mut c Client) quit() ! {
+	c.send_str('QUIT\r\n')!
+	c.expect_reply(.close)!
 	if c.encrypted {
-		c.ssl_conn.shutdown()?
+		c.ssl_conn.shutdown()!
 	} else {
-		c.conn.close()?
+		c.conn.close()!
 	}
 	c.is_open = false
 	c.encrypted = false
 }
 
-fn (mut c Client) connect_ssl() ? {
-	c.ssl_conn = ssl.new_ssl_conn()?
+fn (mut c Client) connect_ssl() ! {
+	c.ssl_conn = ssl.new_ssl_conn()!
 	c.ssl_conn.connect(mut c.conn, c.server) or {
 		return error('Connecting to server using OpenSSL failed: $err')
 	}
@@ -136,10 +136,10 @@ fn (mut c Client) connect_ssl() ? {
 }
 
 // expect_reply checks if the SMTP server replied with the expected reply code
-fn (mut c Client) expect_reply(expected ReplyCode) ? {
+fn (mut c Client) expect_reply(expected ReplyCode) ! {
 	mut str := ''
 	for {
-		str = c.reader.read_line()?
+		str = c.reader.read_line()!
 		if str.len < 4 {
 			return error('Invalid SMTP response: $str')
 		}
@@ -167,7 +167,7 @@ fn (mut c Client) expect_reply(expected ReplyCode) ? {
 }
 
 [inline]
-fn (mut c Client) send_str(s string) ? {
+fn (mut c Client) send_str(s string) ! {
 	$if smtp_debug ? {
 		eprintln('\n\n[SEND START]')
 		eprint(s.trim_space())
@@ -175,27 +175,27 @@ fn (mut c Client) send_str(s string) ? {
 	}
 
 	if c.encrypted {
-		c.ssl_conn.write(s.bytes())?
+		c.ssl_conn.write(s.bytes())!
 	} else {
-		c.conn.write(s.bytes())?
+		c.conn.write(s.bytes())!
 	}
 }
 
 [inline]
-fn (mut c Client) send_ehlo() ? {
-	c.send_str('EHLO $c.server\r\n')?
-	c.expect_reply(.action_ok)?
+fn (mut c Client) send_ehlo() ! {
+	c.send_str('EHLO $c.server\r\n')!
+	c.expect_reply(.action_ok)!
 }
 
 [inline]
-fn (mut c Client) send_starttls() ? {
-	c.send_str('STARTTLS\r\n')?
-	c.expect_reply(.ready)?
-	c.connect_ssl()?
+fn (mut c Client) send_starttls() ! {
+	c.send_str('STARTTLS\r\n')!
+	c.expect_reply(.ready)!
+	c.connect_ssl()!
 }
 
 [inline]
-fn (mut c Client) send_auth() ? {
+fn (mut c Client) send_auth() ! {
 	if c.username.len == 0 {
 		return
 	}
@@ -206,28 +206,28 @@ fn (mut c Client) send_auth() ? {
 	sb.write_string(c.password)
 	a := sb.str()
 	auth := 'AUTH PLAIN ${base64.encode_str(a)}\r\n'
-	c.send_str(auth)?
-	c.expect_reply(.auth_ok)?
+	c.send_str(auth)!
+	c.expect_reply(.auth_ok)!
 }
 
-fn (mut c Client) send_mailfrom(from string) ? {
-	c.send_str('MAIL FROM: <$from>\r\n')?
-	c.expect_reply(.action_ok)?
+fn (mut c Client) send_mailfrom(from string) ! {
+	c.send_str('MAIL FROM: <$from>\r\n')!
+	c.expect_reply(.action_ok)!
 }
 
-fn (mut c Client) send_mailto(to string) ? {
+fn (mut c Client) send_mailto(to string) ! {
 	for rcpt in to.split(';') {
-		c.send_str('RCPT TO: <$rcpt>\r\n')?
-		c.expect_reply(.action_ok)?
+		c.send_str('RCPT TO: <$rcpt>\r\n')!
+		c.expect_reply(.action_ok)!
 	}
 }
 
-fn (mut c Client) send_data() ? {
-	c.send_str('DATA\r\n')?
-	c.expect_reply(.mail_start)?
+fn (mut c Client) send_data() ! {
+	c.send_str('DATA\r\n')!
+	c.expect_reply(.mail_start)!
 }
 
-fn (mut c Client) send_body(cfg Mail) ? {
+fn (mut c Client) send_body(cfg Mail) ! {
 	is_html := cfg.body_type == .html
 	date := cfg.date.custom_format('ddd, D MMM YYYY HH:mm ZZ')
 	nonascii_subject := cfg.subject.bytes().any(it < u8(` `) || it > u8(`~`))
@@ -253,6 +253,6 @@ fn (mut c Client) send_body(cfg Mail) ? {
 	sb.write_string('\r\n\r\n')
 	sb.write_string(base64.encode_str(cfg.body))
 	sb.write_string('\r\n.\r\n')
-	c.send_str(sb.str())?
-	c.expect_reply(.action_ok)?
+	c.send_str(sb.str())!
+	c.expect_reply(.action_ok)!
 }

vlib/net/socket.v

@@ -6,6 +6,6 @@ pub:
 }
 
 // address gets the address of a socket
-pub fn (s &Socket) address() ?Addr {
+pub fn (s &Socket) address() !Addr {
 	return addr_from_socket_handle(s.handle)
 }

vlib/net/ssl/ssl_d_use_openssl.v

@@ -12,7 +12,7 @@ pub struct SSLConnectConfig {
 }
 
 // new_ssl_conn returns a new SSLConn with the given config.
-pub fn new_ssl_conn(config SSLConnectConfig) ?&SSLConn {
+pub fn new_ssl_conn(config SSLConnectConfig) !&SSLConn {
 	c := openssl.new_ssl_conn(config.SSLConnectConfig) or { return err }
 	return &SSLConn{c}
 }

vlib/net/ssl/ssl_notd_use_openssl.v

@@ -12,7 +12,7 @@ pub struct SSLConnectConfig {
 }
 
 // new_ssl_conn returns a new SSLConn with the given config.
-pub fn new_ssl_conn(config SSLConnectConfig) ?&SSLConn {
+pub fn new_ssl_conn(config SSLConnectConfig) !&SSLConn {
 	c := mbedtls.new_ssl_conn(config.SSLConnectConfig) or { return err }
 	return &SSLConn{c}
 }

vlib/net/tcp.v

@@ -21,7 +21,7 @@ mut:
 	is_blocking    bool
 }
 
-pub fn dial_tcp(address string) ?&TcpConn {
+pub fn dial_tcp(address string) !&TcpConn {
 	addrs := resolve_addrs_fuzzy(address, .tcp) or {
 		return error('$err.msg(); could not resolve address $address in dial_tcp')
 	}
@@ -64,7 +64,7 @@ pub fn dial_tcp(address string) ?&TcpConn {
 }
 
 // bind local address and dial.
-pub fn dial_tcp_with_bind(saddr string, laddr string) ?&TcpConn {
+pub fn dial_tcp_with_bind(saddr string, laddr string) !&TcpConn {
 	addrs := resolve_addrs_fuzzy(saddr, .tcp) or {
 		return error('$err.msg(); could not resolve address $saddr in dial_tcp_with_bind')
 	}
@@ -94,15 +94,15 @@ pub fn dial_tcp_with_bind(saddr string, laddr string) ?&TcpConn {
 	return error('dial_tcp_with_bind failed for address $saddr')
 }
 
-pub fn (mut c TcpConn) close() ? {
+pub fn (mut c TcpConn) close() ! {
 	$if trace_tcp ? {
 		eprintln('    TcpConn.close | c.sock.handle: ${c.sock.handle:6}')
 	}
-	c.sock.close()?
+	c.sock.close()!
 }
 
-pub fn (c TcpConn) read_ptr(buf_ptr &u8, len int) ?int {
-	mut res := wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))?
+pub fn (c TcpConn) read_ptr(buf_ptr &u8, len int) !int {
+	mut res := wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))!
 	$if trace_tcp ? {
 		eprintln('<<< TcpConn.read_ptr  | c.sock.handle: $c.sock.handle | buf_ptr: ${ptr_str(buf_ptr)} len: $len | res: $res')
 	}
@@ -115,8 +115,8 @@ pub fn (c TcpConn) read_ptr(buf_ptr &u8, len int) ?int {
 	}
 	code := error_code()
 	if code == int(error_ewouldblock) {
-		c.wait_for_read()?
-		res = wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))?
+		c.wait_for_read()!
+		res = wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))!
 		$if trace_tcp ? {
 			eprintln('<<< TcpConn.read_ptr  | c.sock.handle: $c.sock.handle | buf_ptr: ${ptr_str(buf_ptr)} len: $len | res: $res')
 		}
@@ -128,9 +128,9 @@ pub fn (c TcpConn) read_ptr(buf_ptr &u8, len int) ?int {
 		}
 		return socket_error(res)
 	} else {
-		wrap_error(code)?
+		wrap_error(code)!
 	}
-	return none
+	return error('none')
 }
 
 pub fn (c TcpConn) read(mut buf []u8) !int {
@@ -142,15 +142,15 @@ pub fn (c TcpConn) read(mut buf []u8) !int {
 	}
 }
 
-pub fn (mut c TcpConn) read_deadline() ?time.Time {
+pub fn (mut c TcpConn) read_deadline() !time.Time {
 	if c.read_deadline.unix == 0 {
 		return c.read_deadline
 	}
-	return none
+	return error('none')
 }
 
 // write_ptr blocks and attempts to write all data
-pub fn (mut c TcpConn) write_ptr(b &u8, len int) ?int {
+pub fn (mut c TcpConn) write_ptr(b &u8, len int) !int {
 	$if trace_tcp ? {
 		eprintln(
 			'>>> TcpConn.write_ptr | c.sock.handle: $c.sock.handle | b: ${ptr_str(b)} len: $len |\n' +
@@ -173,10 +173,10 @@ pub fn (mut c TcpConn) write_ptr(b &u8, len int) ?int {
 			if sent < 0 {
 				code := error_code()
 				if code == int(error_ewouldblock) {
-					c.wait_for_write()?
+					c.wait_for_write()!
 					continue
 				} else {
-					wrap_error(code)?
+					wrap_error(code)!
 				}
 			}
 			total_sent += sent
@@ -186,12 +186,12 @@ pub fn (mut c TcpConn) write_ptr(b &u8, len int) ?int {
 }
 
 // write blocks and attempts to write all data
-pub fn (mut c TcpConn) write(bytes []u8) ?int {
+pub fn (mut c TcpConn) write(bytes []u8) !int {
 	return c.write_ptr(bytes.data, bytes.len)
 }
 
 // write_string blocks and attempts to write all data
-pub fn (mut c TcpConn) write_string(s string) ?int {
+pub fn (mut c TcpConn) write_string(s string) !int {
 	return c.write_ptr(s.str, s.len)
 }
 
@@ -199,11 +199,11 @@ pub fn (mut c TcpConn) set_read_deadline(deadline time.Time) {
 	c.read_deadline = deadline
 }
 
-pub fn (mut c TcpConn) write_deadline() ?time.Time {
+pub fn (mut c TcpConn) write_deadline() !time.Time {
 	if c.write_deadline.unix == 0 {
 		return c.write_deadline
 	}
-	return none
+	return error('none')
 }
 
 pub fn (mut c TcpConn) set_write_deadline(deadline time.Time) {
@@ -227,31 +227,31 @@ pub fn (mut c TcpConn) set_write_timeout(t time.Duration) {
 }
 
 [inline]
-pub fn (c TcpConn) wait_for_read() ? {
+pub fn (c TcpConn) wait_for_read() ! {
 	return wait_for_read(c.sock.handle, c.read_deadline, c.read_timeout)
 }
 
 [inline]
-pub fn (mut c TcpConn) wait_for_write() ? {
+pub fn (mut c TcpConn) wait_for_write() ! {
 	return wait_for_write(c.sock.handle, c.write_deadline, c.write_timeout)
 }
 
-pub fn (c &TcpConn) peer_addr() ?Addr {
+pub fn (c &TcpConn) peer_addr() !Addr {
 	mut addr := Addr{
 		addr: AddrData{
 			Ip6: Ip6{}
 		}
 	}
 	mut size := sizeof(Addr)
-	socket_error_message(C.getpeername(c.sock.handle, voidptr(&addr), &size), 'peer_addr failed')?
+	socket_error_message(C.getpeername(c.sock.handle, voidptr(&addr), &size), 'peer_addr failed')!
 	return addr
 }
 
-pub fn (c &TcpConn) peer_ip() ?string {
-	return c.peer_addr()?.str()
+pub fn (c &TcpConn) peer_ip() !string {
+	return c.peer_addr()!.str()
 }
 
-pub fn (c &TcpConn) addr() ?Addr {
+pub fn (c &TcpConn) addr() !Addr {
 	return c.sock.address()
 }
 
@@ -268,7 +268,7 @@ mut:
 	accept_deadline time.Time
 }
 
-pub fn listen_tcp(family AddrFamily, saddr string) ?&TcpListener {
+pub fn listen_tcp(family AddrFamily, saddr string) !&TcpListener {
 	s := new_tcp_socket(family) or { return error('$err.msg(); could not create new socket') }
 
 	addrs := resolve_addrs(saddr, family, .tcp) or {
@@ -280,8 +280,8 @@ pub fn listen_tcp(family AddrFamily, saddr string) ?&TcpListener {
 
 	// cast to the correct type
 	alen := addr.len()
-	socket_error_message(C.bind(s.handle, voidptr(&addr), alen), 'binding to $saddr failed')?
-	socket_error_message(C.listen(s.handle, 128), 'listening on $saddr failed')?
+	socket_error_message(C.bind(s.handle, voidptr(&addr), alen), 'binding to $saddr failed')!
+	socket_error_message(C.listen(s.handle, 128), 'listening on $saddr failed')!
 	return &TcpListener{
 		sock: s
 		accept_deadline: no_deadline
@@ -289,19 +289,19 @@ pub fn listen_tcp(family AddrFamily, saddr string) ?&TcpListener {
 	}
 }
 
-pub fn (mut l TcpListener) accept() ?&TcpConn {
+pub fn (mut l TcpListener) accept() !&TcpConn {
 	$if trace_tcp ? {
 		eprintln('    TcpListener.accept | l.sock.handle: ${l.sock.handle:6}')
 	}
 	mut new_handle := C.accept(l.sock.handle, 0, 0)
 	if new_handle <= 0 {
-		l.wait_for_accept()?
+		l.wait_for_accept()!
 		new_handle = C.accept(l.sock.handle, 0, 0)
 		if new_handle == -1 || new_handle == 0 {
 			return error('accept failed')
 		}
 	}
-	new_sock := tcp_socket_from_handle(new_handle)?
+	new_sock := tcp_socket_from_handle(new_handle)!
 	$if trace_tcp ? {
 		eprintln('    TcpListener.accept | << new_sock.handle: ${new_sock.handle:6}')
 	}
@@ -312,7 +312,7 @@ pub fn (mut l TcpListener) accept() ?&TcpConn {
 	}
 }
 
-pub fn (c &TcpListener) accept_deadline() ?time.Time {
+pub fn (c &TcpListener) accept_deadline() !time.Time {
 	if c.accept_deadline.unix != 0 {
 		return c.accept_deadline
 	}
@@ -331,15 +331,15 @@ pub fn (mut c TcpListener) set_accept_timeout(t time.Duration) {
 	c.accept_timeout = t
 }
 
-pub fn (mut c TcpListener) wait_for_accept() ? {
+pub fn (mut c TcpListener) wait_for_accept() ! {
 	return wait_for_read(c.sock.handle, c.accept_deadline, c.accept_timeout)
 }
 
-pub fn (mut c TcpListener) close() ? {
-	c.sock.close()?
+pub fn (mut c TcpListener) close() ! {
+	c.sock.close()!
 }
 
-pub fn (c &TcpListener) addr() ?Addr {
+pub fn (c &TcpListener) addr() !Addr {
 	return c.sock.address()
 }
 
@@ -347,8 +347,8 @@ struct TcpSocket {
 	Socket
 }
 
-fn new_tcp_socket(family AddrFamily) ?TcpSocket {
-	handle := socket_error(C.socket(family, SocketType.tcp, 0))?
+fn new_tcp_socket(family AddrFamily) !TcpSocket {
+	handle := socket_error(C.socket(family, SocketType.tcp, 0))!
 	mut s := TcpSocket{
 		handle: handle
 	}
@@ -362,20 +362,20 @@ fn new_tcp_socket(family AddrFamily) ?TcpSocket {
 
 	// TODO(emily):
 	// Move this to its own function on the socket
-	s.set_option_int(.reuse_addr, 1)?
+	s.set_option_int(.reuse_addr, 1)!
 
 	$if !net_blocking_sockets ? {
 		$if windows {
 			t := u32(1) // true
-			socket_error(C.ioctlsocket(handle, fionbio, &t))?
+			socket_error(C.ioctlsocket(handle, fionbio, &t))!
 		} $else {
-			socket_error(C.fcntl(handle, C.F_SETFL, C.fcntl(handle, C.F_GETFL) | C.O_NONBLOCK))?
+			socket_error(C.fcntl(handle, C.F_SETFL, C.fcntl(handle, C.F_GETFL) | C.O_NONBLOCK))!
 		}
 	}
 	return s
 }
 
-fn tcp_socket_from_handle(sockfd int) ?TcpSocket {
+fn tcp_socket_from_handle(sockfd int) !TcpSocket {
 	mut s := TcpSocket{
 		handle: sockfd
 	}
@@ -383,22 +383,22 @@ fn tcp_socket_from_handle(sockfd int) ?TcpSocket {
 		eprintln('    tcp_socket_from_handle | s.handle: ${s.handle:6}')
 	}
 	// s.set_option_bool(.reuse_addr, true)?
-	s.set_option_int(.reuse_addr, 1)?
+	s.set_option_int(.reuse_addr, 1)!
 	s.set_dualstack(true) or {
 		// Not ipv6, we dont care
 	}
 	$if !net_blocking_sockets ? {
 		$if windows {
 			t := u32(1) // true
-			socket_error(C.ioctlsocket(sockfd, fionbio, &t))?
+			socket_error(C.ioctlsocket(sockfd, fionbio, &t))!
 		} $else {
-			socket_error(C.fcntl(sockfd, C.F_SETFL, C.fcntl(sockfd, C.F_GETFL) | C.O_NONBLOCK))?
+			socket_error(C.fcntl(sockfd, C.F_SETFL, C.fcntl(sockfd, C.F_GETFL) | C.O_NONBLOCK))!
 		}
 	}
 	return s
 }
 
-pub fn (mut s TcpSocket) set_option_bool(opt SocketOption, value bool) ? {
+pub fn (mut s TcpSocket) set_option_bool(opt SocketOption, value bool) ! {
 	// TODO reenable when this `in` operation works again
 	// if opt !in opts_can_set {
 	// 	return err_option_not_settable
@@ -407,21 +407,21 @@ pub fn (mut s TcpSocket) set_option_bool(opt SocketOption, value bool) ? {
 	// 	return err_option_wrong_type
 	// }
 	x := int(value)
-	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &x, sizeof(int)))?
+	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &x, sizeof(int)))!
 }
 
-pub fn (mut s TcpSocket) set_dualstack(on bool) ? {
+pub fn (mut s TcpSocket) set_dualstack(on bool) ! {
 	x := int(!on)
 	socket_error(C.setsockopt(s.handle, C.IPPROTO_IPV6, int(SocketOption.ipv6_only), &x,
-		sizeof(int)))?
+		sizeof(int)))!
 }
 
-pub fn (mut s TcpSocket) set_option_int(opt SocketOption, value int) ? {
-	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &value, sizeof(int)))?
+pub fn (mut s TcpSocket) set_option_int(opt SocketOption, value int) ! {
+	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &value, sizeof(int)))!
 }
 
 // bind a local rddress for TcpSocket
-pub fn (mut s TcpSocket) bind(addr string) ? {
+pub fn (mut s TcpSocket) bind(addr string) ! {
 	addrs := resolve_addrs(addr, AddrFamily.ip, .tcp) or {
 		return error('$err.msg(); could not resolve address $addr')
 	}
@@ -436,11 +436,11 @@ pub fn (mut s TcpSocket) bind(addr string) ? {
 	}
 }
 
-fn (mut s TcpSocket) close() ? {
+fn (mut s TcpSocket) close() ! {
 	return shutdown(s.handle)
 }
 
-fn (mut s TcpSocket) @select(test Select, timeout time.Duration) ?bool {
+fn (mut s TcpSocket) @select(test Select, timeout time.Duration) !bool {
 	return @select(s.handle, test, timeout)
 }
 
@@ -448,7 +448,7 @@ const (
 	connect_timeout = 5 * time.second
 )
 
-fn (mut s TcpSocket) connect(a Addr) ? {
+fn (mut s TcpSocket) connect(a Addr) ! {
 	$if !net_blocking_sockets ? {
 		res := C.connect(s.handle, voidptr(&a), a.len())
 		if res == 0 {
@@ -467,7 +467,7 @@ fn (mut s TcpSocket) connect(a Addr) ? {
 			// determine whether connect() completed successfully (SO_ERROR is zero) or
 			// unsuccessfully (SO_ERROR is one of the usual error codes  listed  here,
 			// ex‐ plaining the reason for the failure).
-			write_result := s.@select(.write, net.connect_timeout)?
+			write_result := s.@select(.write, net.connect_timeout)!
 			err := 0
 			len := sizeof(err)
 			xyz := C.getsockopt(s.handle, C.SOL_SOCKET, C.SO_ERROR, &err, &len)
@@ -476,17 +476,17 @@ fn (mut s TcpSocket) connect(a Addr) ? {
 			}
 			if write_result {
 				if xyz == 0 {
-					wrap_error(err)?
+					wrap_error(err)!
 					return
 				}
 				return
 			}
 			return err_timed_out
 		}
-		wrap_error(ecode)?
+		wrap_error(ecode)!
 		return
 	} $else {
 		x := C.connect(s.handle, voidptr(&a), a.len())
-		socket_error(x)?
+		socket_error(x)!
 	}
 }

vlib/net/tcp_read_line.v

@@ -22,14 +22,14 @@ pub fn (mut con TcpConn) get_blocking() bool {
 // when state is true, or non blocking (false).
 // The default for `net` tcp connections is the non blocking mode.
 // Calling .read_line will set the connection to blocking mode.
-pub fn (mut con TcpConn) set_blocking(state bool) ? {
+pub fn (mut con TcpConn) set_blocking(state bool) ! {
 	con.is_blocking = state
 	$if windows {
 		mut t := u32(0)
 		if !con.is_blocking {
 			t = 1
 		}
-		socket_error(C.ioctlsocket(con.sock.handle, fionbio, &t))?
+		socket_error(C.ioctlsocket(con.sock.handle, fionbio, &t))!
 	} $else {
 		mut flags := C.fcntl(con.sock.handle, C.F_GETFL, 0)
 		if state {
@@ -37,7 +37,7 @@ pub fn (mut con TcpConn) set_blocking(state bool) ? {
 		} else {
 			flags |= C.O_NONBLOCK
 		}
-		socket_error(C.fcntl(con.sock.handle, C.F_SETFL, flags))?
+		socket_error(C.fcntl(con.sock.handle, C.F_SETFL, flags))!
 	}
 }
 

vlib/net/udp.v

@@ -27,8 +27,8 @@ mut:
 	write_timeout  time.Duration
 }
 
-pub fn dial_udp(raddr string) ?&UdpConn {
-	addrs := resolve_addrs_fuzzy(raddr, .udp)?
+pub fn dial_udp(raddr string) !&UdpConn {
+	addrs := resolve_addrs_fuzzy(raddr, .udp)!
 
 	for addr in addrs {
 		// create a local socket for this
@@ -43,7 +43,7 @@ pub fn dial_udp(raddr string) ?&UdpConn {
 		}
 	}
 
-	return none
+	return error('none')
 }
 
 // pub fn dial_udp(laddr string, raddr string) ?&UdpConn {
@@ -58,46 +58,46 @@ pub fn dial_udp(raddr string) ?&UdpConn {
 // 	}
 // }
 
-pub fn (mut c UdpConn) write_ptr(b &u8, len int) ?int {
+pub fn (mut c UdpConn) write_ptr(b &u8, len int) !int {
 	remote := c.sock.remote() or { return err_no_udp_remote }
 	return c.write_to_ptr(remote, b, len)
 }
 
-pub fn (mut c UdpConn) write(buf []u8) ?int {
+pub fn (mut c UdpConn) write(buf []u8) !int {
 	return c.write_ptr(buf.data, buf.len)
 }
 
-pub fn (mut c UdpConn) write_string(s string) ?int {
+pub fn (mut c UdpConn) write_string(s string) !int {
 	return c.write_ptr(s.str, s.len)
 }
 
-pub fn (mut c UdpConn) write_to_ptr(addr Addr, b &u8, len int) ?int {
+pub fn (mut c UdpConn) write_to_ptr(addr Addr, b &u8, len int) !int {
 	res := C.sendto(c.sock.handle, b, len, 0, voidptr(&addr), addr.len())
 	if res >= 0 {
 		return res
 	}
 	code := error_code()
 	if code == int(error_ewouldblock) {
-		c.wait_for_write()?
-		socket_error(C.sendto(c.sock.handle, b, len, 0, voidptr(&addr), addr.len()))?
+		c.wait_for_write()!
+		socket_error(C.sendto(c.sock.handle, b, len, 0, voidptr(&addr), addr.len()))!
 	} else {
-		wrap_error(code)?
+		wrap_error(code)!
 	}
-	return none
+	return error('none')
 }
 
 // write_to blocks and writes the buf to the remote addr specified
-pub fn (mut c UdpConn) write_to(addr Addr, buf []u8) ?int {
+pub fn (mut c UdpConn) write_to(addr Addr, buf []u8) !int {
 	return c.write_to_ptr(addr, buf.data, buf.len)
 }
 
 // write_to_string blocks and writes the buf to the remote addr specified
-pub fn (mut c UdpConn) write_to_string(addr Addr, s string) ?int {
+pub fn (mut c UdpConn) write_to_string(addr Addr, s string) !int {
 	return c.write_to_ptr(addr, s.str, s.len)
 }
 
 // read reads from the socket into buf up to buf.len returning the number of bytes read
-pub fn (mut c UdpConn) read(mut buf []u8) ?(int, Addr) {
+pub fn (mut c UdpConn) read(mut buf []u8) !(int, Addr) {
 	mut addr := Addr{
 		addr: AddrData{
 			Ip6: Ip6{}
@@ -105,40 +105,40 @@ pub fn (mut c UdpConn) read(mut buf []u8) ?(int, Addr) {
 	}
 	len := sizeof(Addr)
 	mut res := wrap_read_result(C.recvfrom(c.sock.handle, voidptr(buf.data), buf.len,
-		0, voidptr(&addr), &len))?
+		0, voidptr(&addr), &len))!
 	if res > 0 {
 		return res, addr
 	}
 	code := error_code()
 	if code == int(error_ewouldblock) {
-		c.wait_for_read()?
+		c.wait_for_read()!
 		// same setup as in tcp
 		res = wrap_read_result(C.recvfrom(c.sock.handle, voidptr(buf.data), buf.len, 0,
-			voidptr(&addr), &len))?
-		res2 := socket_error(res)?
+			voidptr(&addr), &len))!
+		res2 := socket_error(res)!
 		return res2, addr
 	} else {
-		wrap_error(code)?
+		wrap_error(code)!
 	}
-	return none
+	return error('none')
 }
 
-pub fn (c &UdpConn) read_deadline() ?time.Time {
+pub fn (c &UdpConn) read_deadline() !time.Time {
 	if c.read_deadline.unix == 0 {
 		return c.read_deadline
 	}
-	return none
+	return error('none')
 }
 
 pub fn (mut c UdpConn) set_read_deadline(deadline time.Time) {
 	c.read_deadline = deadline
 }
 
-pub fn (c &UdpConn) write_deadline() ?time.Time {
+pub fn (c &UdpConn) write_deadline() !time.Time {
 	if c.write_deadline.unix == 0 {
 		return c.write_deadline
 	}
-	return none
+	return error('none')
 }
 
 pub fn (mut c UdpConn) set_write_deadline(deadline time.Time) {
@@ -162,12 +162,12 @@ pub fn (mut c UdpConn) set_write_timeout(t time.Duration) {
 }
 
 [inline]
-pub fn (mut c UdpConn) wait_for_read() ? {
+pub fn (mut c UdpConn) wait_for_read() ! {
 	return wait_for_read(c.sock.handle, c.read_deadline, c.read_timeout)
 }
 
 [inline]
-pub fn (mut c UdpConn) wait_for_write() ? {
+pub fn (mut c UdpConn) wait_for_write() ! {
 	return wait_for_write(c.sock.handle, c.write_deadline, c.write_timeout)
 }
 
@@ -176,27 +176,27 @@ pub fn (c &UdpConn) str() string {
 	return 'UdpConn'
 }
 
-pub fn (mut c UdpConn) close() ? {
+pub fn (mut c UdpConn) close() ! {
 	return c.sock.close()
 }
 
-pub fn listen_udp(laddr string) ?&UdpConn {
-	addrs := resolve_addrs_fuzzy(laddr, .udp)?
+pub fn listen_udp(laddr string) !&UdpConn {
+	addrs := resolve_addrs_fuzzy(laddr, .udp)!
 	// TODO(emily):
 	// here we are binding to the first address
 	// and that is probably not ideal
 	addr := addrs[0]
 	return &UdpConn{
-		sock: new_udp_socket(addr)?
+		sock: new_udp_socket(addr)!
 		read_timeout: net.udp_default_read_timeout
 		write_timeout: net.udp_default_write_timeout
 	}
 }
 
-fn new_udp_socket(local_addr Addr) ?&UdpSocket {
+fn new_udp_socket(local_addr Addr) !&UdpSocket {
 	family := local_addr.family()
 
-	sockfd := socket_error(C.socket(family, SocketType.udp, 0))?
+	sockfd := socket_error(C.socket(family, SocketType.udp, 0))!
 	mut s := &UdpSocket{
 		handle: sockfd
 		l: local_addr
@@ -207,28 +207,28 @@ fn new_udp_socket(local_addr Addr) ?&UdpSocket {
 		}
 	}
 
-	s.set_option_bool(.reuse_addr, true)?
+	s.set_option_bool(.reuse_addr, true)!
 
 	if family == .ip6 {
-		s.set_dualstack(true)?
+		s.set_dualstack(true)!
 	}
 
 	$if !net_blocking_sockets ? {
 		// NOTE: refer to comments in tcp.v
 		$if windows {
 			t := u32(1) // true
-			socket_error(C.ioctlsocket(sockfd, fionbio, &t))?
+			socket_error(C.ioctlsocket(sockfd, fionbio, &t))!
 		} $else {
-			socket_error(C.fcntl(sockfd, C.F_SETFD, C.O_NONBLOCK))?
+			socket_error(C.fcntl(sockfd, C.F_SETFD, C.O_NONBLOCK))!
 		}
 	}
 
 	// cast to the correct type
-	socket_error(C.bind(s.handle, voidptr(&local_addr), local_addr.len()))?
+	socket_error(C.bind(s.handle, voidptr(&local_addr), local_addr.len()))!
 	return s
 }
 
-fn new_udp_socket_for_remote(raddr Addr) ?&UdpSocket {
+fn new_udp_socket_for_remote(raddr Addr) !&UdpSocket {
 	// Invent a sutible local address for this remote addr
 	// Appease compiler
 	mut addr := Addr{
@@ -246,20 +246,20 @@ fn new_udp_socket_for_remote(raddr Addr) ?&UdpSocket {
 			addr = new_ip6(0, addr_ip6_any)
 		}
 		.unix {
-			addr = temp_unix()?
+			addr = temp_unix()!
 		}
 		else {
 			panic('Invalid family')
 		}
 	}
-	mut sock := new_udp_socket(addr)?
+	mut sock := new_udp_socket(addr)!
 	sock.has_r = true
 	sock.r = raddr
 
 	return sock
 }
 
-pub fn (mut s UdpSocket) set_option_bool(opt SocketOption, value bool) ? {
+pub fn (mut s UdpSocket) set_option_bool(opt SocketOption, value bool) ! {
 	// TODO reenable when this `in` operation works again
 	// if opt !in opts_can_set {
 	// 	return err_option_not_settable
@@ -268,26 +268,26 @@ pub fn (mut s UdpSocket) set_option_bool(opt SocketOption, value bool) ? {
 	// 	return err_option_wrong_type
 	// }
 	x := int(value)
-	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &x, sizeof(int)))?
+	socket_error(C.setsockopt(s.handle, C.SOL_SOCKET, int(opt), &x, sizeof(int)))!
 }
 
-pub fn (mut s UdpSocket) set_dualstack(on bool) ? {
+pub fn (mut s UdpSocket) set_dualstack(on bool) ! {
 	x := int(!on)
 	socket_error(C.setsockopt(s.handle, C.IPPROTO_IPV6, int(SocketOption.ipv6_only), &x,
-		sizeof(int)))?
+		sizeof(int)))!
 }
 
-fn (mut s UdpSocket) close() ? {
+fn (mut s UdpSocket) close() ! {
 	return shutdown(s.handle)
 }
 
-fn (mut s UdpSocket) @select(test Select, timeout time.Duration) ?bool {
+fn (mut s UdpSocket) @select(test Select, timeout time.Duration) !bool {
 	return @select(s.handle, test, timeout)
 }
 
-fn (s &UdpSocket) remote() ?Addr {
+fn (s &UdpSocket) remote() !Addr {
 	if s.has_r {
 		return s.r
 	}
-	return none
+	return error('none')
 }

vlib/net/udp_test.v

@@ -24,7 +24,7 @@ fn echo_server(mut c net.UdpConn) {
 
 const server_addr = '127.0.0.1:40003'
 
-fn echo() ? {
+fn echo() ! {
 	mut c := net.dial_udp(server_addr) or { panic('could not net.dial_udp: $err') }
 	defer {
 		c.close() or {}
@@ -48,7 +48,7 @@ fn echo() ? {
 
 	println('Got "$buf.bytestr()"')
 
-	c.close()?
+	c.close()!
 }
 
 fn test_udp() {

vlib/net/unix/common.v

@@ -12,18 +12,18 @@ fn C.SUN_LEN(ptr &C.sockaddr_un) int
 fn C.strncpy(&char, &char, int)
 
 // Shutdown shutsdown a socket and closes it
-fn shutdown(handle int) ? {
+fn shutdown(handle int) ! {
 	$if windows {
 		C.shutdown(handle, C.SD_BOTH)
-		net.socket_error(C.closesocket(handle))?
+		net.socket_error(C.closesocket(handle))!
 	} $else {
 		C.shutdown(handle, C.SHUT_RDWR)
-		net.socket_error(C.close(handle))?
+		net.socket_error(C.close(handle))!
 	}
 }
 
 // Select waits for an io operation (specified by parameter `test`) to be available
-fn @select(handle int, test Select, timeout time.Duration) ?bool {
+fn @select(handle int, test Select, timeout time.Duration) !bool {
 	set := C.fd_set{}
 
 	C.FD_ZERO(&set)
@@ -47,13 +47,13 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 
 	match test {
 		.read {
-			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, &set, C.NULL, C.NULL, timeval_timeout))!
 		}
 		.write {
-			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, &set, C.NULL, timeval_timeout))!
 		}
 		.except {
-			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))?
+			net.socket_error(C.@select(handle + 1, C.NULL, C.NULL, &set, timeval_timeout))!
 		}
 	}
 
@@ -61,13 +61,13 @@ fn @select(handle int, test Select, timeout time.Duration) ?bool {
 }
 
 // wait_for_common wraps the common wait code
-fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ? {
+fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test Select) ! {
 	if deadline.unix == 0 {
 		// do not accept negative timeout
 		if timeout < 0 {
 			return net.err_timed_out
 		}
-		ready := @select(handle, test, timeout)?
+		ready := @select(handle, test, timeout)!
 		if ready {
 			return
 		}
@@ -82,7 +82,7 @@ fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test S
 		return net.err_timed_out
 	}
 
-	ready := @select(handle, test, d_timeout)?
+	ready := @select(handle, test, d_timeout)!
 	if ready {
 		return
 	}
@@ -90,12 +90,12 @@ fn wait_for_common(handle int, deadline time.Time, timeout time.Duration, test S
 }
 
 // wait_for_write waits for a write io operation to be available
-fn wait_for_write(handle int, deadline time.Time, timeout time.Duration) ? {
+fn wait_for_write(handle int, deadline time.Time, timeout time.Duration) ! {
 	return wait_for_common(handle, deadline, timeout, .write)
 }
 
 // wait_for_read waits for a read io operation to be available
-fn wait_for_read(handle int, deadline time.Time, timeout time.Duration) ? {
+fn wait_for_read(handle int, deadline time.Time, timeout time.Duration) ! {
 	return wait_for_common(handle, deadline, timeout, .read)
 }
 
@@ -120,9 +120,9 @@ const (
 )
 
 [inline]
-fn wrap_read_result(result int) ?int {
+fn wrap_read_result(result int) !int {
 	if result != 0 {
 		return result
 	}
-	return none
+	return error('none')
 }

vlib/net/unix/stream_nix.v

@@ -40,23 +40,23 @@ fn error_code() int {
 	return C.errno
 }
 
-fn new_stream_socket() ?StreamSocket {
-	sockfd := net.socket_error(C.socket(net.AddrFamily.unix, net.SocketType.tcp, 0))?
+fn new_stream_socket() !StreamSocket {
+	sockfd := net.socket_error(C.socket(net.AddrFamily.unix, net.SocketType.tcp, 0))!
 	mut s := StreamSocket{
 		handle: sockfd
 	}
 	return s
 }
 
-fn (mut s StreamSocket) close() ? {
+fn (mut s StreamSocket) close() ! {
 	return shutdown(s.handle)
 }
 
-fn (mut s StreamSocket) @select(test Select, timeout time.Duration) ?bool {
+fn (mut s StreamSocket) @select(test Select, timeout time.Duration) !bool {
 	return @select(s.handle, test, timeout)
 }
 
-fn (mut s StreamSocket) connect(a string) ? {
+fn (mut s StreamSocket) connect(a string) ! {
 	if a.len >= max_sun_path {
 		return error('Socket path too long! Max length: ${max_sun_path - 1} chars.')
 	}
@@ -73,12 +73,12 @@ fn (mut s StreamSocket) connect(a string) ? {
 		return
 	}
 	_ := error_code()
-	write_result := s.@select(.write, unix.connect_timeout)?
+	write_result := s.@select(.write, unix.connect_timeout)!
 	if write_result {
 		// succeeded
 		return
 	}
-	except_result := s.@select(.except, unix.connect_timeout)?
+	except_result := s.@select(.except, unix.connect_timeout)!
 	if except_result {
 		return net.err_connect_failed
 	}
@@ -86,11 +86,11 @@ fn (mut s StreamSocket) connect(a string) ? {
 	return net.err_connect_timed_out
 }
 
-pub fn listen_stream(sock string) ?&StreamListener {
+pub fn listen_stream(sock string) !&StreamListener {
 	if sock.len >= max_sun_path {
 		return error('Socket path too long! Max length: ${max_sun_path - 1} chars.')
 	}
-	mut s := new_stream_socket()?
+	mut s := new_stream_socket()!
 	s.path = sock
 	mut addr := C.sockaddr_un{}
 	unsafe { C.memset(&addr, 0, sizeof(C.sockaddr_un)) }
@@ -98,19 +98,19 @@ pub fn listen_stream(sock string) ?&StreamListener {
 	unsafe { C.strncpy(&addr.sun_path[0], &char(sock.str), max_sun_path) }
 	size := C.SUN_LEN(&addr)
 	if os.exists(sock) {
-		os.rm(sock)?
+		os.rm(sock)!
 	}
-	net.socket_error(C.bind(s.handle, voidptr(&addr), size))?
-	os.chmod(sock, 0o777)?
-	net.socket_error(C.listen(s.handle, 128))?
+	net.socket_error(C.bind(s.handle, voidptr(&addr), size))!
+	os.chmod(sock, 0o777)!
+	net.socket_error(C.listen(s.handle, 128))!
 	return &StreamListener{
 		sock: s
 	}
 }
 
-pub fn connect_stream(path string) ?&StreamConn {
-	mut s := new_stream_socket()?
-	s.connect(path)?
+pub fn connect_stream(path string) !&StreamConn {
+	mut s := new_stream_socket()!
+	s.connect(path)!
 	return &StreamConn{
 		sock: s
 		read_timeout: unix.unix_default_read_timeout
@@ -118,10 +118,10 @@ pub fn connect_stream(path string) ?&StreamConn {
 	}
 }
 
-pub fn (mut l StreamListener) accept() ?&StreamConn {
+pub fn (mut l StreamListener) accept() !&StreamConn {
 	mut new_handle := C.accept(l.sock.handle, 0, 0)
 	if new_handle <= 0 {
-		l.wait_for_accept()?
+		l.wait_for_accept()!
 		new_handle = C.accept(l.sock.handle, 0, 0)
 		if new_handle == -1 || new_handle == 0 {
 			return error('accept failed')
@@ -137,7 +137,7 @@ pub fn (mut l StreamListener) accept() ?&StreamConn {
 	}
 }
 
-pub fn (c &StreamListener) accept_deadline() ?time.Time {
+pub fn (c &StreamListener) accept_deadline() !time.Time {
 	if c.accept_deadline.unix != 0 {
 		return c.accept_deadline
 	}
@@ -156,21 +156,21 @@ pub fn (mut c StreamListener) set_accept_timeout(t time.Duration) {
 	c.accept_timeout = t
 }
 
-pub fn (mut c StreamListener) wait_for_accept() ? {
+pub fn (mut c StreamListener) wait_for_accept() ! {
 	return wait_for_read(c.sock.handle, c.accept_deadline, c.accept_timeout)
 }
 
-pub fn (mut c StreamListener) close() ? {
-	os.rm(c.sock.path)?
-	c.sock.close()?
+pub fn (mut c StreamListener) close() ! {
+	os.rm(c.sock.path)!
+	c.sock.close()!
 }
 
-pub fn (mut c StreamConn) close() ? {
-	c.sock.close()?
+pub fn (mut c StreamConn) close() ! {
+	c.sock.close()!
 }
 
 // write_ptr blocks and attempts to write all data
-pub fn (mut c StreamConn) write_ptr(b &u8, len int) ?int {
+pub fn (mut c StreamConn) write_ptr(b &u8, len int) !int {
 	$if trace_unix ? {
 		eprintln(
 			'>>> StreamConn.write_ptr | c.sock.handle: $c.sock.handle | b: ${ptr_str(b)} len: $len |\n' +
@@ -186,10 +186,10 @@ pub fn (mut c StreamConn) write_ptr(b &u8, len int) ?int {
 			if sent < 0 {
 				code := error_code()
 				if code == int(error_ewouldblock) {
-					c.wait_for_write()?
+					c.wait_for_write()!
 					continue
 				} else {
-					net.wrap_error(code)?
+					net.wrap_error(code)!
 				}
 			}
 			total_sent += sent
@@ -199,17 +199,17 @@ pub fn (mut c StreamConn) write_ptr(b &u8, len int) ?int {
 }
 
 // write blocks and attempts to write all data
-pub fn (mut c StreamConn) write(bytes []u8) ?int {
+pub fn (mut c StreamConn) write(bytes []u8) !int {
 	return c.write_ptr(bytes.data, bytes.len)
 }
 
 // write_string blocks and attempts to write all data
-pub fn (mut c StreamConn) write_string(s string) ?int {
+pub fn (mut c StreamConn) write_string(s string) !int {
 	return c.write_ptr(s.str, s.len)
 }
 
-pub fn (mut c StreamConn) read_ptr(buf_ptr &u8, len int) ?int {
-	mut res := wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))?
+pub fn (mut c StreamConn) read_ptr(buf_ptr &u8, len int) !int {
+	mut res := wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))!
 	$if trace_unix ? {
 		eprintln('<<< StreamConn.read_ptr  | c.sock.handle: $c.sock.handle | buf_ptr: ${ptr_str(buf_ptr)} len: $len | res: $res')
 	}
@@ -218,38 +218,38 @@ pub fn (mut c StreamConn) read_ptr(buf_ptr &u8, len int) ?int {
 	}
 	code := error_code()
 	if code == int(error_ewouldblock) {
-		c.wait_for_read()?
-		res = wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))?
+		c.wait_for_read()!
+		res = wrap_read_result(C.recv(c.sock.handle, voidptr(buf_ptr), len, 0))!
 		$if trace_unix ? {
 			eprintln('<<< StreamConn.read_ptr  | c.sock.handle: $c.sock.handle | buf_ptr: ${ptr_str(buf_ptr)} len: $len | res: $res')
 		}
 		return net.socket_error(res)
 	} else {
-		net.wrap_error(code)?
+		net.wrap_error(code)!
 	}
 	return net.socket_error(code)
 }
 
-pub fn (mut c StreamConn) read(mut buf []u8) ?int {
+pub fn (mut c StreamConn) read(mut buf []u8) !int {
 	return c.read_ptr(buf.data, buf.len)
 }
 
-pub fn (mut c StreamConn) read_deadline() ?time.Time {
+pub fn (mut c StreamConn) read_deadline() !time.Time {
 	if c.read_deadline.unix == 0 {
 		return c.read_deadline
 	}
-	return none
+	return error('none')
 }
 
 pub fn (mut c StreamConn) set_read_deadline(deadline time.Time) {
 	c.read_deadline = deadline
 }
 
-pub fn (mut c StreamConn) write_deadline() ?time.Time {
+pub fn (mut c StreamConn) write_deadline() !time.Time {
 	if c.write_deadline.unix == 0 {
 		return c.write_deadline
 	}
-	return none
+	return error('none')
 }
 
 pub fn (mut c StreamConn) set_write_deadline(deadline time.Time) {
@@ -273,12 +273,12 @@ pub fn (mut c StreamConn) set_write_timeout(t time.Duration) {
 }
 
 [inline]
-pub fn (mut c StreamConn) wait_for_read() ? {
+pub fn (mut c StreamConn) wait_for_read() ! {
 	return wait_for_read(c.sock.handle, c.read_deadline, c.read_timeout)
 }
 
 [inline]
-pub fn (mut c StreamConn) wait_for_write() ? {
+pub fn (mut c StreamConn) wait_for_write() ! {
 	return wait_for_write(c.sock.handle, c.write_deadline, c.write_timeout)
 }
 

vlib/net/unix/unix_test.v

@@ -27,22 +27,22 @@ fn handle_conn(mut c unix.StreamConn) {
 	}
 }
 
-fn echo_server(mut l unix.StreamListener) ? {
+fn echo_server(mut l unix.StreamListener) ! {
 	for {
 		mut new_conn := l.accept() or { continue }
 		go handle_conn(mut new_conn)
 	}
 }
 
-fn echo() ? {
-	mut c := unix.connect_stream(test_port)?
+fn echo() ! {
+	mut c := unix.connect_stream(test_port)!
 	defer {
 		c.close() or {}
 	}
 	data := 'Hello from vlib/net!'
-	c.write_string(data)?
+	c.write_string(data)!
 	mut buf := []u8{len: 4096}
-	read := c.read(mut buf)?
+	read := c.read(mut buf)!
 	assert read == data.len
 	for i := 0; i < read; i++ {
 		assert buf[i] == data[i]