os: make exec() return ?Result with exit code and output

compiler/cgen.v

@@ -261,7 +261,7 @@ fn build_thirdparty_obj_file(flag string) {
 	res := os.exec('$cc -fPIC -c -o $obj_path $cfiles') or {
 		panic(err)
 	}
-	println(res) 
+	println(res.output) 
 } 
 
 fn os_name_to_ifdef(name string) string { 

compiler/main.v

@@ -924,7 +924,7 @@ mut args := ''
 		'/usr/lib/x86_64-linux-gnu/crtn.o') or {
 			panic(err)
 		}
-		println(ress)
+		println(ress.output)
 		println('linux cross compilation done. resulting binary: "$v.out_name"')
 	}
 	if !v.pref.is_debug && v.out_name_c != 'v.c' && v.out_name_c != 'v_macos.c' {
@@ -1336,7 +1336,7 @@ fn run_repl() []string {
 			s := os.exec('$vexe run $file -repl') or {
 				panic(err)
 			}
-			vals := s.split('\n')
+			vals := s.output.split('\n')
 			for i:=0; i < vals.len; i++ {
 				println(vals[i])
 			}
@@ -1354,7 +1354,7 @@ fn run_repl() []string {
 				panic(err)
 			}
 			lines << line
-			vals := s.split('\n')
+			vals := s.output.split('\n')
 			for i:=0; i<vals.len; i++ {
 				println(vals[i])
 			}
@@ -1418,18 +1418,18 @@ fn update_v() {
 	s := os.exec('git -C "$vroot" pull --rebase origin master') or {
 		panic(err)
 	}
-	println(s) 
+	println(s.output) 
 	$if windows { 
 		os.mv('$vroot/v.exe', '$vroot/v_old.exe') 
 		s2 := os.exec('$vroot/make.bat') or {
 			panic(err)
 		}
-		println(s2) 
+		println(s2.output) 
 	} $else { 
 		s2 := os.exec('make -C "$vroot"') or {
 			panic(err)
 		}
-		println(s2) 
+		println(s2.output) 
 	} 
 } 
 

compiler/msvc.v

@@ -145,7 +145,7 @@ fn find_vs() ?VsInstallation {
 	}
 	// println('res: "$res"')
 
-	version := os.read_file('$res\\VC\\Auxiliary\\Build\\Microsoft.VCToolsVersion.default.txt') or {
+	version := os.read_file('$res.output\\VC\\Auxiliary\\Build\\Microsoft.VCToolsVersion.default.txt') or {
 		println('Unable to find msvc version')
 		return error('Unable to find vs installation')
 	}
@@ -158,11 +158,11 @@ fn find_vs() ?VsInstallation {
 		version
 	}
 
-	lib_path := '$res\\VC\\Tools\\MSVC\\$v\\lib\\x64'
-	include_path := '$res\\VC\\Tools\\MSVC\\$v\\include'
+	lib_path := '$res.output\\VC\\Tools\\MSVC\\$v\\lib\\x64'
+	include_path := '$res.output\\VC\\Tools\\MSVC\\$v\\include'
 
 	if os.file_exists('$lib_path\\vcruntime.lib') {
-		p := '$res\\VC\\Tools\\MSVC\\$v\\bin\\Hostx64\\x64'
+		p := '$res.output\\VC\\Tools\\MSVC\\$v\\bin\\Hostx64\\x64'
 
 		// println('$lib_path $include_path')
 
@@ -406,6 +406,6 @@ fn build_thirdparty_obj_file_with_msvc(flag string) {
 	res := os.exec('""$msvc.exe_path\\cl.exe" /volatile:ms /Z7 $include_string /c $cfiles /Fo"$obj_path" /D_UNICODE /DUNICODE"') or {
 		panic(err)
 	}
-	println(res)
+	println(res.output)
 }
 

compiler/parser.v

@@ -2385,9 +2385,11 @@ fn (p mut Parser) factor() string {
 		typ = p.if_st(true, 0)
 		return typ
 	default:
+		if p.pref.is_verbose || p.pref.is_debug { 
 			next := p.peek()
-		println('PREV=${p.prev_tok.str()}')
-		println('.neXT=${next.str()}')
+			println('prev=${p.prev_tok.str()}')
+			println('next=${next.str()}')
+		} 
 		p.error('unexpected token: `${p.tok.str()}`')
 	}
 	p.next()// TODO everything should next()

vlib/os/os.v

@@ -307,18 +307,6 @@ pub fn (f File) close() {
 }
 
 // system starts the specified command, waits for it to complete, and returns its code.
-pub fn system(cmd string) int {
-	mut ret := int(0)
-	$if windows {
-		ret = C._wsystem(cmd.to_wide())
-	} $else {
-		ret = C.system(cmd.str) 
-	}
-	if ret == -1 {
-		os.print_c_errno()
-	}
-	return ret
-}
 
 fn popen(path string) *FILE {
 	$if windows {
@@ -341,12 +329,19 @@ fn pclose(f *FILE) int {
 	}
 }
 
+struct Result {
+pub: 
+	exit_code int 
+	output string
+	//stderr string // TODO 
+} 
+
 // exec starts the specified command, waits for it to complete, and returns its output.
-pub fn exec(_cmd string) ?string {
-	cmd := '$_cmd 2>&1'
-	f := popen(cmd)
+pub fn exec(cmd string) ?Result {
+	pcmd := '$cmd 2>&1'
+	f := popen(pcmd)
 	if isnil(f) {
-		return error('popen $cmd failed')
+		return error('exec("$cmd") failed')
 	}
 	buf := [1000]byte 
 	mut res := ''
@@ -354,11 +349,27 @@ pub fn exec(_cmd string) ?string {
 		res += tos(buf, strlen(buf)) 
 	}
 	res = res.trim_space()
-	status_code := pclose(f)/256
-	if status_code != 0 {
-		return error(res)
+	exit_code := pclose(f)/256
+	//if exit_code != 0 {
+		//return error(res)
+	//}
+	return Result {
+		output: res
+		exit_code: exit_code 
 	} 
-	return res
+}
+
+pub fn system(cmd string) int {
+	mut ret := int(0)
+	$if windows {
+		ret = C._wsystem(cmd.to_wide())
+	} $else {
+		ret = C.system(cmd.str) 
+	}
+	if ret == -1 {
+		os.print_c_errno()
+	}
+	return ret
 }
 
 // `getenv` returns the value of the environment variable named by the key.