os: clean up file functions, use optionals

compiler/cgen.v

@@ -31,9 +31,15 @@ mut:
 }
 
 fn new_cgen(out_name_c string) *CGen {
+	path:='$TmpPath/$out_name_c'
+	out := os.create(path) or {
+		println('failed to create $path') 
+		return &CGen{} 
+} 
+	 
 	gen := &CGen {
-		out_path: '$TmpPath/$out_name_c'
-		out: os.create('$TmpPath/$out_name_c')
+		out_path: path 
+		out: out 
 	}
 	return gen
 }

compiler/jsgen.v

@@ -104,7 +104,8 @@ string res = tos2("");
 		enc += '  cJSON_AddItemToObject(o,  "$name", $enc_name(val.$name)); \n'
 	}
 	// cJSON_delete
-	p.cgen.fns << '$dec return opt_ok(res); \n}'
+	//p.cgen.fns << '$dec return opt_ok(res); \n}'
+	p.cgen.fns << '$dec return opt_ok(res, sizeof(res)); \n}'
 	p.cgen.fns << '/*enc start*/ $enc return o;}'
 }
 

compiler/main.v

@@ -618,7 +618,7 @@ mut args := ''
 		println('linux cross compilation done. resulting binary: "$v.out_name"')
 	}
 	if !v.pref.is_debug && v.out_name_c != 'v.c' && v.out_name_c != 'v_macos.c' {
-		os.rm('$TmpPath/$v.out_name_c') 
+		//os.rm('$TmpPath/$v.out_name_c') 
 	} 
 }
 
@@ -882,7 +882,8 @@ fn new_v(args[]string) *V {
 	if os.file_exists(vroot_path) {
 		mut vroot := os.read_file(vroot_path) or {
 			break
-		}
+		} 
+		//mut vroot := os.read_file(vroot_path) 
 		vroot=vroot.trim_space() 
 		if os.dir_exists(vroot) && os.dir_exists(vroot + '/vlib/builtin') {
 			lang_dir = vroot

compiler/parser.v

@@ -239,7 +239,10 @@ fn (p mut Parser) parse() {
 				p.check_unused_variables()
 			}
 			if false && !p.first_run() && p.fileis('main.v') {
-				out := os.create('/var/tmp/fmt.v')
+				out := os.create('/var/tmp/fmt.v') or {
+					panic('failed to create fmt.v') 
+					return 
+} 
 				out.writeln(p.scanner.fmt_out.str())
 				out.close()
 			}
@@ -670,14 +673,14 @@ fn (p mut Parser) error(s string) {
 //q := "SDF" 
 	// Dump all vars and types for debugging
 	if false {
-		file_types := os.create('$TmpPath/types')
-		file_vars := os.create('$TmpPath/vars')
+		//file_types := os.create('$TmpPath/types')
+		//file_vars := os.create('$TmpPath/vars')
 		// ////debug("ALL T", q.J(p.table.types))
 		// os.write_to_file('/var/tmp/lang.types', '')//pes(p.table.types))
 		// //debug("ALL V", q.J(p.table.vars))
 		// os.write_to_file('/var/tmp/lang.vars', q.J(p.table.vars))
-		file_types.close()
-		file_vars.close()
+		//file_types.close()
+		//file_vars.close()
 	}
 	if !p.pref.is_repl {
 		println('pass=$p.run fn=`$p.cur_fn.name`')
@@ -1082,7 +1085,8 @@ fn (p mut Parser) assign_statement(v Var, ph int, is_map bool) {
 		println('allowing option asss')
 		expr := p.cgen.cur_line.right(pos)
 		left := p.cgen.cur_line.left(pos)
-		p.cgen.cur_line = left + 'opt_ok($expr)'
+		//p.cgen.cur_line = left + 'opt_ok($expr)'
+		p.cgen.cur_line = left + 'opt_ok($expr, sizeof($expr_type))'
 	}
 	else if !p.builtin_pkg && !p.check_types_no_throw(expr_type, p.assigned_type) {
 		p.scanner.line_nr--
@@ -3030,8 +3034,9 @@ fn (p mut Parser) return_st() {
 			expr_type := p.bool_expression()
 			// Automatically wrap an object inside an option if the function returns an option
 			if p.cur_fn.typ.ends_with(expr_type) && p.cur_fn.typ.starts_with('Option_') {
+				//p.cgen.set_placeholder(ph, 'opt_ok(& ')
 				p.cgen.set_placeholder(ph, 'opt_ok(& ')
-				p.gen(')')
+				p.gen(', sizeof($expr_type))')
 			}
 			p.check_types(expr_type, p.cur_fn.typ)
 		}

compiler/scanner.v

@@ -32,6 +32,7 @@ fn new_scanner(file_path string) *Scanner {
 	if !os.file_exists(file_path) {
 		panic('"$file_path" doesn\'t exist')
 	}
+	//text := os.read_file(file_path) 
 	text := os.read_file(file_path) or {
 		panic('scanner: failed to open "$file_path"')
 		return &Scanner{}

vlib/builtin/builtin.v

@@ -94,23 +94,11 @@ fn _strlen(s byteptr) int {
 	return C.strlen(s)
 }
 
-// `fn foo() ?Foo { return foo }` => `fn foo() ?Foo { return opt_ok(foo); }`
-fn opt_ok(data voidptr) Option {
-	return Option {
-		data: data
-		ok: true
-	}
-}
 
 fn memdup(src voidptr, sz int) voidptr {
 	mem := malloc(sz)
 	return C.memcpy(mem, src, sz)
 }
 
-pub fn error(s string) Option {
-	return Option {
-		error: s
-	}
-}
 
 

vlib/builtin/option.v

@@ -5,8 +5,27 @@
 module builtin
 
 struct Option {
-	data  voidptr
+	data [255] byte 
 	error string
 	ok    bool
 }
 
+// `fn foo() ?Foo { return foo }` => `fn foo() ?Foo { return opt_ok(foo); }`
+fn opt_ok(data voidptr, size int) Option {
+	if size > 255 {
+		panic('option size too big: $size (max is 255)') 
+	} 
+	res := Option { 
+		ok: true
+	}
+	C.memcpy(res.data, data, size) 
+	return res 
+}
+
+pub fn error(s string) Option {
+	return Option {
+		error: s
+	}
+}
+
+

vlib/os/os.v

@@ -105,7 +105,34 @@ fn parse_windows_cmd_line(cmd byteptr) []string {
 }
 
 // read_file reads the file in `path` and returns the contents.
-pub fn read_file(path string) ?string {
+//pub fn read_file(path string) ?string {
+pub fn read_file(path string) ?string { 
+	mut res := ''
+	mut mode := 'r' 
+	777  // TODO 
+	// Need 'rb' on windows to avoid the \r\n mess. 
+	$if windows {
+		mode = 'rb' 
+	} 
+	cpath := path.cstr()
+	fp := C.fopen(cpath, mode.cstr()) 
+	if isnil(fp) {
+		return error('failed to open file "$path"')
+		//panic('failed to open file "$path"')
+	}
+	C.fseek(fp, 0, SEEK_END)
+	fsize := C.ftell(fp)
+	// C.fseek(fp, 0, SEEK_SET)  // same as C.rewind(fp) below
+	C.rewind(fp)
+	mut str := malloc(fsize + 1)
+	C.fread(str, fsize, 1, fp)
+	C.fclose(fp)
+	str[fsize] = 0
+	res = tos(str, fsize)
+	return res
+}
+
+pub fn read_file_opt(path string) ?string { 
 	mut res := ''
 	mut mode := 'r' 
 	777  // TODO 
@@ -178,36 +205,38 @@ fn read_ulines(path string) []ustring {
 	return ulines
 }
 
-// TODO return `File?`
-pub fn open(path string) File {
-	return open_file(path)
-}
-
-fn open_file(file string) File {
-	return create_file2(file, 'r')
-}
-
-// `create` creates a file at a specified location and returns a writable `File` object.
-pub fn create(path string) File {
-	return create_file2(path, 'w')
-}
-
-fn create_file_a(file string) File {
-	return create_file2(file, 'a')
-}
-
-fn open_file_a(file string) File {
-	return create_file2(file, 'a')
-}
-
-fn create_file2(file, mode string) File {
-	res := File {
-		cfile: C.fopen(file.cstr(), mode.cstr())
+pub fn open(path string) ?File {
+	cpath := path.cstr() 
+	file := File {
+		cfile: C.fopen(cpath, 'r') 
 	}
-	if isnil(res.cfile) {
-		println('coudlnt create file "$file"')
+	if isnil(file.cfile) {
+		return error('failed to open file "$path"')
 	}
-	return res
+	return file 
+}
+
+// create creates a file at a specified location and returns a writable `File` object.
+pub fn create(path string) ?File {
+	cpath := path.cstr() 
+	file := File {
+		cfile: C.fopen(cpath, 'w') 
+	}
+	if isnil(file.cfile) {
+		return error('failed to create file "$path"')
+	}
+	return file 
+}
+
+pub fn open_append(path string) ?File {
+	cpath := path.cstr() 
+	file := File {
+		cfile: C.fopen(cpath, 'a') 
+	}
+	if isnil(file.cfile) {
+		return error('failed to create file "$path"')
+	}
+	return file 
 }
 
 pub fn (f File) write(s string) {
@@ -243,15 +272,6 @@ pub fn (f File) close() {
 	C.fclose(f.cfile)
 }
 
-fn close_file(fp *FILE) {
-	$if windows {
-	}
-	if isnil(fp) {
-		return
-	}
-	C.fclose(fp)
-}
-
 // system starts the specified command, waits for it to complete, and returns its code.
 pub fn system(cmd string) int {
 	ret := C.system(cmd.cstr()) 
@@ -479,7 +499,9 @@ pub fn home_dir() string {
 
 // write_file writes text data to a file in `path`. 
 pub fn write_file(path, text string) {
-	f := os.create(path)
+	f := os.create(path) or {
+		return 
+	} 
 	f.write(text)
 	f.close()
 }