various fixes:

- missing return in import code
- proper propagation of flags to various components
- better error message when source position is missing
- cleanups

R=r
OCL=13676
CL=13676

usr/gri/gosrc/compilation.go

@@ -17,22 +17,18 @@ import Printer "printer"
 
 
 export Compile
-func Compile(file_name string, verbose int) {
+func Compile(comp *Globals.Compilation, file_name string) {
 	src, ok := sys.readfile(file_name);
 	if !ok {
 		print "cannot open ", file_name, "\n"
 		return;
 	}
 	
-	Universe.Init();  // TODO eventually this should be only needed once
-	
-	comp := Globals.NewCompilation();
-
 	scanner := new(Scanner.Scanner);
 	scanner.Open(file_name, src);
 
 	parser := new(Parser.Parser);
-	parser.Open(comp, scanner, verbose);
+	parser.Open(comp, scanner);
 
 	print "parsing ", file_name, "\n";
 	parser.ParseProgram();
@@ -40,12 +36,9 @@ func Compile(file_name string, verbose int) {
 		return;
 	}
 	
-	/*
 	// export
-	exp := new(Export.Exporter);
-	exp.Export(comp, Utils.FixExt(Utils.BaseName(file_name)));
-	
-	// print export
+	if comp.flags.semantic_checks {
 		Printer.PrintObject(comp, comp.pkgs[0].obj, false);
-	*/
+		Export.Export(comp, file_name);
+	}
 }

usr/gri/gosrc/decls.go

@@ -121,4 +121,4 @@ func (p *T4) m5(a, b int, c float) (z T5, ok bool) {
 
 export c0, c1, v2, v3
 export T0, T1, T4, T4, T4, M0, M5, I2, f0, f1
-// export Node0, Node1 // this fails
+export Node0, Node1

usr/gri/gosrc/export.go

@@ -4,13 +4,13 @@
 
 package Exporter
 
+import Utils "utils"
 import Globals "globals"
 import Object "object"
 import Type "type"
 import Universe "universe"
 
 
-export Exporter  // really only want to export Export()
 type Exporter struct {
 	comp *Globals.Compilation;
 	debug bool;
@@ -65,7 +65,7 @@ func (E *Exporter) WriteString(s string) {
 }
 
 
-func (E *Exporter) WriteObjTag(tag int) {
+func (E *Exporter) WriteObjectTag(tag int) {
 	if tag < 0 {
 		panic "tag < 0";
 	}
@@ -113,23 +113,12 @@ func (E *Exporter) WriteScope(scope *Globals.Scope) {
 		print " {";
 	}
 
-	// determine number of objects to export
-	n := 0;
-	for p := scope.entries.first; p != nil; p = p.next {
-		if p.obj.exported {
-			n++;
-		}			
-	}
-	E.WriteInt(n);
-	
-	// export the objects, if any
-	if n > 0 {
 	for p := scope.entries.first; p != nil; p = p.next {
 		if p.obj.exported {
 			E.WriteObject(p.obj);
 		}
 	}
-	}
+	E.WriteObjectTag(0);  // terminator
 	
 	if E.debug {
 		print " }";
@@ -144,11 +133,11 @@ func (E *Exporter) WriteObject(obj *Globals.Object) {
 
 	if obj.kind == Object.TYPE && obj.typ.obj == obj {
 		// primary type object - handled entirely by WriteType()
-		E.WriteObjTag(Object.PTYPE);
+		E.WriteObjectTag(Object.PTYPE);
 		E.WriteType(obj.typ);
 
 	} else {
-		E.WriteObjTag(obj.kind);
+		E.WriteObjectTag(obj.kind);
 		E.WriteString(obj.ident);
 		E.WriteType(obj.typ);
 		E.WritePackage(E.comp.pkgs[obj.pnolev]);
@@ -252,7 +241,7 @@ func (E *Exporter) WritePackage(pkg *Globals.Package) {
 
 func (E *Exporter) Export(comp* Globals.Compilation, file_name string) {
 	E.comp = comp;
-	E.debug = false;
+	E.debug = comp.flags.debug;
 	E.pos = 0;
 	E.pkg_ref = 0;
 	E.type_ref = 0;
@@ -275,12 +264,7 @@ func (E *Exporter) Export(comp* Globals.Compilation, file_name string) {
 	
 	pkg := comp.pkgs[0];
 	E.WritePackage(pkg);
-	for p := pkg.scope.entries.first; p != nil; p = p.next {
-		if p.obj.exported {
-			E.WriteObject(p.obj);
-		}
-	}
-	E.WriteObjTag(0);
+	E.WriteScope(pkg.scope);
 	
 	if E.debug {
 		print "\n(", E.pos, " bytes)\n";
@@ -293,3 +277,10 @@ func (E *Exporter) Export(comp* Globals.Compilation, file_name string) {
 		panic "export failed";
 	}
 }
+
+
+export Export
+func Export(comp* Globals.Compilation, pkg_name string) {
+	var E Exporter;
+	(&E).Export(comp, Utils.FixExt(Utils.BaseName(pkg_name)));
+}

usr/gri/gosrc/globals.go

@@ -75,8 +75,17 @@ type Scope struct {
 }
 
 
+export Flags;
+type Flags struct {
+	debug bool;
+	semantic_checks bool;
+	verbose int;
+}
+
+
 export Compilation
 type Compilation struct {
+	flags *Flags;
 	// TODO use open arrays eventually
 	pkgs [256] *Package;  // pkgs[0] is the current package
 	npkgs int;
@@ -134,8 +143,9 @@ func NewScope(parent *Scope) *Scope {
 
 
 export NewCompilation;
-func NewCompilation() *Compilation {
+func NewCompilation(flags *Flags) *Compilation {
 	comp := new(Compilation);
+	comp.flags = flags;
 	return comp;
 }
 

usr/gri/gosrc/go.go

@@ -5,19 +5,22 @@
 package main
 
 import Build "build"
+import Globals "globals"
 import Compilation "compilation"
 
 
+// For now we are not using the flags package to minimize
+// external dependencies, and because the requirements are
+// very minimal at this point.
+
 func PrintHelp() {
   print "go in go (", Build.time, ")\n";
   print "usage:\n";
-  print "  go { -v | -vv | file }\n";
-  /*
-  printf("flags:\n");
-  for (int i = 0; Flags[i].name != NULL; i++) {
-    printf("  %s  %s\n", Flags[i].name, Flags[i].help);
-  }
-  */
+  print "  go { flag | file }\n";
+  print "  -d  print debug information\n";
+  print "  -s  enable semantic checks\n";
+  print "  -v  verbose mode\n";
+  print "  -vv  very verbose mode\n";
 }
 
 
@@ -27,17 +30,22 @@ func main() {
 		sys.exit(1);
 	}
 	
-	verbose := 0;
+	// collect flags and files
+	flags := new(Globals.Flags);
+	files := Globals.NewList();
 	for i := 1; i < sys.argc(); i++ {
-		switch sys.argv(i) {
-		case "-v":
-			verbose = 1;
-			continue;
-		case "-vv":
-			verbose = 2;
-			continue;
+		switch arg := sys.argv(i); arg {
+		case "-d": flags.debug = true;
+		case "-s": flags.semantic_checks = true;
+		case "-v": flags.verbose = 1;
+		case "-vv": flags.verbose = 2;
+		default: files.AddStr(arg);
+		}
 	}
 	
-		Compilation.Compile(sys.argv(i), verbose);
+	// compile files
+	for p := files.first; p != nil; p = p.next {
+		comp := Globals.NewCompilation(flags);
+		Compilation.Compile(comp, p.str);
 	}
 }

usr/gri/gosrc/import.go

@@ -4,13 +4,13 @@
 
 package Importer
 
+import Utils "utils"
 import Globals "globals"
 import Object "object"
 import Type "type"
 import Universe "universe"
 
 
-export Importer  // really only want to export Import()
 type Importer struct {
 	comp *Globals.Compilation;
 	debug bool;
@@ -74,7 +74,7 @@ func (I *Importer) ReadString() string {
 }
 
 
-func (I *Importer) ReadObjTag() int {
+func (I *Importer) ReadObjectTag() int {
 	tag := I.ReadInt();
 	if tag < 0 {
 		panic "tag < 0";
@@ -125,14 +125,21 @@ func (I *Importer) ReadScope() *Globals.Scope {
 	}
 
 	scope := Globals.NewScope(nil);
-	for n := I.ReadInt(); n > 0; n-- {
-		tag := I.ReadObjTag();
-		scope.Insert(I.ReadObject(tag));
+	for {
+		tag := I.ReadObjectTag();
+		if tag == 0 {
+			break;
+		}
+		// InsertImport only needed for package scopes
+		// but ok to use always
+		scope.InsertImport(I.ReadObject(tag));
 	}
 	
 	if I.debug {
 		print " }";
 	}
+	
+	return scope;
 }
 
 
@@ -229,13 +236,12 @@ func (I *Importer) ReadType() *Globals.Type {
 
 	case Type.FUNCTION:
 		typ.flags = I.ReadInt();
-		fallthrough;
-	case Type.STRUCT: fallthrough;
-	case Type.INTERFACE:
 		typ.scope = I.ReadScope();
 
-	case Type.POINTER: fallthrough;
-	case Type.REFERENCE:
+	case Type.STRUCT, Type.INTERFACE:
+		typ.scope = I.ReadScope();
+
+	case Type.POINTER, Type.REFERENCE:
 		typ.elt = I.ReadType();
 	}
 
@@ -275,7 +281,7 @@ func (I *Importer) ReadPackage() *Globals.Package {
 
 func (I *Importer) Import(comp* Globals.Compilation, file_name string) *Globals.Package {
 	I.comp = comp;
-	I.debug = false;
+	I.debug = comp.flags.debug;
 	I.buf = "";
 	I.pos = 0;
 	I.npkgs = 0;
@@ -302,7 +308,7 @@ func (I *Importer) Import(comp* Globals.Compilation, file_name string) *Globals.
 
 	pkg := I.ReadPackage();
 	for {
-		tag := I.ReadObjTag();
+		tag := I.ReadObjectTag();
 		if tag == 0 {
 			break;
 		}
@@ -317,3 +323,10 @@ func (I *Importer) Import(comp* Globals.Compilation, file_name string) *Globals.
 	
 	return pkg;
 }
+
+
+export Import
+func Import(comp* Globals.Compilation, pkg_name string) *Globals.Package {
+	var I Importer;
+	return (&I).Import(comp, Utils.FixExt(pkg_name));
+}

usr/gri/gosrc/parser.go

@@ -14,13 +14,10 @@ import Import "import"
 import AST "ast"
 
 
-// So I can submit and have a running parser for now...
-const EnableSemanticTests = false;
-
-
 export Parser
 type Parser struct {
 	comp *Globals.Compilation;
+	semantic_checks bool;
 	verbose, indent int;
 	S *Scanner.Scanner;
 	
@@ -74,9 +71,10 @@ func (P *Parser) Next() {
 }
 
 
-func (P *Parser) Open(comp *Globals.Compilation, S *Scanner.Scanner, verbose int) {
+func (P *Parser) Open(comp *Globals.Compilation, S *Scanner.Scanner) {
 	P.comp = comp;
-	P.verbose = verbose;
+	P.semantic_checks = comp.flags.semantic_checks;
+	P.verbose = comp.flags.verbose;
 	P.indent = 0;
 	P.S = S;
 	P.Next();
@@ -132,7 +130,7 @@ func (P *Parser) Lookup(ident string) *Globals.Object {
 
 
 func (P *Parser) DeclareInScope(scope *Globals.Scope, obj *Globals.Object) {
-	if !EnableSemanticTests {
+	if !P.semantic_checks {
 		return;
 	}
 	obj.pnolev = P.level;
@@ -296,7 +294,7 @@ func (P *Parser) ParseQualifiedIdent(pos int, ident string) *Globals.Object {
 		ident = P.ParseIdent();
 	}
 	
-	if EnableSemanticTests {
+	if P.semantic_checks {
 		obj := P.Lookup(ident);
 		if obj == nil {
 			P.Error(pos, `"` + ident + `" is not declared`);
@@ -355,7 +353,7 @@ func (P *Parser) ParseType() *Globals.Type {
 func (P *Parser) ParseTypeName() *Globals.Type {
 	P.Trace("TypeName");
 	
-	if EnableSemanticTests {
+	if P.semantic_checks {
 		pos := P.pos;
 		obj := P.ParseQualifiedIdent(-1, "");
 		typ := obj.typ;
@@ -496,7 +494,7 @@ func (P *Parser) ParseAnonymousSignature() *Globals.Type {
 	
 	if P.tok == Scanner.PERIOD {
 		p0 = sig.entries.len_;
-		if (EnableSemanticTests && p0 != 1) {
+		if (P.semantic_checks && p0 != 1) {
 			P.Error(recv_pos, "must have exactly one receiver")
 			panic "UNIMPLEMENTED (ParseAnonymousSignature)";
 			// TODO do something useful here
@@ -534,7 +532,7 @@ func (P *Parser) ParseNamedSignature() (name string, typ *Globals.Type) {
 		recv_pos := P.pos;
 		P.ParseParameters();
 		p0 = sig.entries.len_;
-		if (EnableSemanticTests && p0 != 1) {
+		if (P.semantic_checks && p0 != 1) {
 			print "p0 = ", p0, "\n";
 			P.Error(recv_pos, "must have exactly one receiver")
 			panic "UNIMPLEMENTED (ParseNamedSignature)";
@@ -653,7 +651,7 @@ func (P *Parser) ParsePointerType() *Globals.Type {
 	P.Expect(Scanner.MUL);
 	typ := Globals.NewType(Type.POINTER);
 	
-	if EnableSemanticTests {
+	if P.semantic_checks {
 		if P.tok == Scanner.IDENT {
 			if P.Lookup(P.val) == nil {
 				// implicit forward declaration
@@ -1122,7 +1120,7 @@ func (P *Parser) ParseExpression() {
 func (P *Parser) ConvertToExprList(pos_list, ident_list, expr_list *Globals.List) {
 	for p, q := pos_list.first, ident_list.first; q != nil; p, q = p.next, q.next {
 		pos, ident := p.val, q.str;
-		if EnableSemanticTests {
+		if P.semantic_checks {
 			obj := P.Lookup(ident);
 			if obj == nil {
 				P.Error(pos, `"` + ident + `" is not declared`);
@@ -1208,24 +1206,24 @@ func (P *Parser) ParseSimpleStat() {
 	switch P.tok {
 	case Scanner.COLON:
 		// label declaration
-		if EnableSemanticTests && ident_list.len_ != 1 {
+		if P.semantic_checks && ident_list.len_ != 1 {
 			P.Error(P.pos, "illegal label declaration");
 		}
 		P.Next();
 		
 	case Scanner.DEFINE:
 		// variable declaration
-		if EnableSemanticTests && ident_list.len_ == 0 {
+		if P.semantic_checks && ident_list.len_ == 0 {
 			P.Error(P.pos, "illegal left-hand side for declaration");
 		}
 		P.Next();
 		pos := P.pos;
 		val_list := P.ParseExpressionList();
-		if EnableSemanticTests && val_list.len_ != ident_list.len_ {
+		if P.semantic_checks && val_list.len_ != ident_list.len_ {
 			P.Error(pos, "number of expressions does not match number of variables");
 		}
 		// declare variables
-		if EnableSemanticTests {
+		if P.semantic_checks {
 			for p, q := pos_list.first, ident_list.first; q != nil; p, q = p.next, q.next {
 				obj := Globals.NewObject(p.val, Object.VAR, q.str);
 				P.Declare(obj);
@@ -1248,13 +1246,13 @@ func (P *Parser) ParseSimpleStat() {
 		P.Next();
 		pos := P.pos;
 		val_list := P.ParseExpressionList();
-		if EnableSemanticTests && val_list.len_ != expr_list.len_ {
+		if P.semantic_checks && val_list.len_ != expr_list.len_ {
 			P.Error(pos, "number of expressions does not match number of variables");
 		}
 		
 	default:
 		P.ConvertToExprList(pos_list, ident_list, expr_list);
-		if EnableSemanticTests && expr_list.len_ != 1 {
+		if P.semantic_checks && expr_list.len_ != 1 {
 			P.Error(P.pos, "no expression list allowed");
 		}
 		if P.tok == Scanner.INC || P.tok == Scanner.DEC {
@@ -1557,11 +1555,10 @@ func (P *Parser) ParseImportSpec() {
 		obj = P.ParseIdentDecl(Object.PACKAGE);
 	}
 	
-	if (EnableSemanticTests && P.tok == Scanner.STRING) {
+	if (P.semantic_checks && P.tok == Scanner.STRING) {
 		// TODO eventually the scanner should strip the quotes
 		pkg_name := P.val[1 : len(P.val) - 1];  // strip quotes
-		imp := new(Import.Importer);
-		pkg := imp.Import(P.comp, Utils.FixExt(Utils.BaseName(pkg_name)));
+		pkg := Import.Import(P.comp, pkg_name);
 		if pkg != nil {
 			if obj == nil {
 				// use original package name
@@ -1776,7 +1773,7 @@ func (P *Parser) ParseDeclaration() {
 // Program
 
 func (P *Parser) ResolveUndefTypes() {
-	if !EnableSemanticTests {
+	if !P.semantic_checks {
 		return;
 	}
 	
@@ -1798,7 +1795,7 @@ func (P *Parser) ResolveUndefTypes() {
 
 
 func (P *Parser) MarkExports() {
-	if !EnableSemanticTests {
+	if !P.semantic_checks {
 		return;
 	}
 	
@@ -1820,7 +1817,7 @@ func (P *Parser) MarkExports() {
 			}
 		} else {
 			// TODO need to report proper src position
-			P.Error(0, `"` + p.str + `" is not declared - cannot be exported`);
+			P.Error(-1, `"` + p.str + `" is not declared - cannot be exported`);
 		}
 	}
 }

usr/gri/gosrc/scanner.go

@@ -4,6 +4,9 @@
 
 package Scanner
 
+import Utils "utils"
+
+
 export
 	ILLEGAL, EOF, IDENT, STRING, NUMBER,
 	COMMA, COLON, SEMICOLON, PERIOD,
@@ -231,6 +234,18 @@ func TokenName(tok int) string {
 }
 
 
+func init() {
+	Keywords = new(map [string] int);
+	
+	for i := KEYWORDS_BEG; i <= KEYWORDS_END; i++ {
+	  Keywords[TokenName(i)] = i;
+	}
+	
+	// Provide column information in error messages for gri only...
+	VerboseMsgs = Utils.GetEnv("USER") == "gri";
+}
+
+
 func is_whitespace(ch int) bool {
 	return ch == ' ' || ch == '\r' || ch == '\n' || ch == '\t';
 }
@@ -370,28 +385,6 @@ bad:
 }
 
 
-func IsUser(username string) bool {
-	for i := 0; i < sys.envc(); i++ {
-		if sys.envv(i) == "USER=" + username {
-			return true;
-		}
-	}
-	return false;
-}
-
-
-func Init() {
-	Keywords = new(map [string] int);
-	
-	for i := KEYWORDS_BEG; i <= KEYWORDS_END; i++ {
-	  Keywords[TokenName(i)] = i;
-	}
-	
-	// Provide column information in error messages for gri only...
-	VerboseMsgs = IsUser("gri");
-}
-
-
 // Compute (line, column) information for a given source position.
 func (S *Scanner) LineCol(pos int) (line, col int) {
 	line = 1;
@@ -416,13 +409,21 @@ func (S *Scanner) LineCol(pos int) (line, col int) {
 func (S *Scanner) Error(pos int, msg string) {
 	const errdist = 10;
 	delta := pos - S.errpos;  // may be negative!
-	if delta < errdist || delta > errdist || S.nerrors == 0 {
+	if delta < 0 {
+		delta = -delta;
+	}
+	if delta > errdist || S.nerrors == 0 /* always report first error */ {
+		print S.filename;
+		if pos >= 0 {
+			// print position
 			line, col := S.LineCol(pos);
 			if VerboseMsgs {
-			print S.filename, ":", line, ":", col, ": ", msg, "\n";
+				print ":", line, ":", col;
 			} else {
-			print S.filename, ":", line,           ": ", msg, "\n";
+				print ":", line;
 			}
+		}
+		print ": ", msg, "\n";
 		S.nerrors++;
 		S.errpos = pos;
 	}
@@ -434,10 +435,6 @@ func (S *Scanner) Error(pos int, msg string) {
 
 
 func (S *Scanner) Open(filename, src string) {
-	if Keywords == nil {
-		Init();
-	}
-
 	S.filename = filename;
 	S.nerrors = 0;
 	S.errpos = 0;

usr/gri/gosrc/universe.go

@@ -101,8 +101,7 @@ func Register(typ *Globals.Type) *Globals.Type {
 }
 
 
-export Init
-func Init() {
+func init() {
 	scope = Globals.NewScope(nil);  // universe has no parent
 	types = Globals.NewList();
 	

usr/gri/gosrc/utils.go

@@ -27,3 +27,16 @@ func FixExt(s string) string {
 	}
 	return s + ".7";
 }
+
+
+export GetEnv
+func GetEnv(key string) string {
+	n := len(key);
+	for i := 0; i < sys.envc(); i++ {
+		v := sys.envv(i);
+		if v[0 : n] == key {
+			return v[n + 1 : len(v)];  // +1: skip "="
+		}
+	}
+	return "";
+}