go AST: First step towards augmenting AST with full type information.

- change ast.Ident back to contain the name and adjust all dependent code
- identifier object information will be added again through an optional
  typechecker phase (in the works).
- remove tracking of scopes in parser - it's easier to do this in a separate
  phase (in the works)
- in godoc, generate popup info table directly instead of through a formatter
  for simpler data flow (at the expense of a little bit more code)

Runs all tests.

As a result of this change, the currently shown popup information
(const, var, type, func, followed by identifier name) will not be
shown anymore temporarily.

R=rsc
CC=golang-dev
https://golang.org/cl/1994041

lib/godoc/source.html

@@ -7,11 +7,8 @@
 <script src="http://www.google.com/jsapi"></script>
 <script src="/doc/popups.js"></script>
 <script>
-var popup_data = [
+{# IdList is HTML-escaped by godoc}
-{.repeated section Data}
+var popup_data = {IdList}
-	'{@|popupInfo}',
-{.end}
-]
 
 google.load("jquery", "1");
 google.setOnLoadCallback(function() {.meta-left}
@@ -19,5 +16,5 @@ google.setOnLoadCallback(function() {.meta-left}
 {.meta-right});
 </script>
 
-{# Source is HTML-escaped elsewhere}
+{# Source is HTML-escaped by godoc}
 <pre>{Source}</pre>

src/cmd/cgo/ast.go

@@ -17,7 +17,7 @@ import (
 )
 
 func parse(name string, flags uint) *ast.File {
-	ast1, err := parser.ParseFile(name, nil, nil, flags)
+	ast1, err := parser.ParseFile(name, nil, flags)
 	if err != nil {
 		if list, ok := err.(scanner.ErrorList); ok {
 			// If err is a scanner.ErrorList, its String will print just
@@ -49,7 +49,7 @@ func (f *File) ReadGo(name string) {
 	ast1 := parse(name, parser.ParseComments)
 	ast2 := parse(name, 0)
 
-	f.Package = ast1.Name.Name()
+	f.Package = ast1.Name.Name
 	f.Name = make(map[string]*Name)
 
 	// In ast1, find the import "C" line and get any extra C preamble.
@@ -135,7 +135,7 @@ func (f *File) saveRef(x interface{}, context string) {
 		// The parser should take care of scoping in the future,
 		// so that we will be able to distinguish a "top-level C"
 		// from a local C.
-		if l, ok := sel.X.(*ast.Ident); ok && l.Name() == "C" {
+		if l, ok := sel.X.(*ast.Ident); ok && l.Name == "C" {
 			i := len(f.Ref)
 			if i >= cap(f.Ref) {
 				new := make([]*Ref, 2*i)
@@ -147,7 +147,7 @@ func (f *File) saveRef(x interface{}, context string) {
 			if context == "as2" {
 				context = "expr"
 			}
-			goname := sel.Sel.Name()
+			goname := sel.Sel.Name
 			name := f.Name[goname]
 			if name == nil {
 				name = &Name{
@@ -212,7 +212,7 @@ func (f *File) saveExport2(x interface{}, context string) {
 	}
 
 	for _, exp := range f.ExpFunc {
-		if exp.Func.Name.Name() == n.Name.Name() {
+		if exp.Func.Name.Name == n.Name.Name {
 			exp.Func = n
 			break
 		}

src/cmd/cgo/gcc.go

@@ -145,7 +145,7 @@ func (p *Package) guessKinds(f *File) []*Name {
 			if _, err := strconv.Atoi(n.Define); err == nil {
 				ok = true
 			} else if n.Define[0] == '"' || n.Define[0] == '\'' {
-				_, err := parser.ParseExpr("", n.Define, nil)
+				_, err := parser.ParseExpr("", n.Define)
 				if err == nil {
 					ok = true
 				}
@@ -801,7 +801,7 @@ func (c *typeConv) Type(dtype dwarf.Type) *Type {
 		t.Go = name // publish before recursive calls
 		switch dt.Kind {
 		case "union", "class":
-			c.typedef[name.Name()] = c.Opaque(t.Size)
+			c.typedef[name.Name] = c.Opaque(t.Size)
 			if t.C == "" {
 				t.C = fmt.Sprintf("typeof(unsigned char[%d])", t.Size)
 			}
@@ -811,7 +811,7 @@ func (c *typeConv) Type(dtype dwarf.Type) *Type {
 				t.C = csyntax
 			}
 			t.Align = align
-			c.typedef[name.Name()] = g
+			c.typedef[name.Name] = g
 		}
 
 	case *dwarf.TypedefType:
@@ -830,8 +830,8 @@ func (c *typeConv) Type(dtype dwarf.Type) *Type {
 		sub := c.Type(dt.Type)
 		t.Size = sub.Size
 		t.Align = sub.Align
-		if _, ok := c.typedef[name.Name()]; !ok {
+		if _, ok := c.typedef[name.Name]; !ok {
-			c.typedef[name.Name()] = sub.Go
+			c.typedef[name.Name] = sub.Go
 		}
 
 	case *dwarf.UcharType:
@@ -875,7 +875,7 @@ func (c *typeConv) Type(dtype dwarf.Type) *Type {
 			}
 			s = strings.Join(strings.Split(s, " ", -1), "") // strip spaces
 			name := c.Ident("_Ctype_" + s)
-			c.typedef[name.Name()] = t.Go
+			c.typedef[name.Name] = t.Go
 			t.Go = name
 		}
 	}

src/cmd/cgo/out.go

@@ -403,9 +403,9 @@ func (p *Package) writeExports(fgo2, fc *os.File) {
 		fmt.Fprintf(fgcc, "}\n")
 
 		// Build the wrapper function compiled by 6c/8c
-		goname := exp.Func.Name.Name()
+		goname := exp.Func.Name.Name
 		if fn.Recv != nil {
-			goname = "_cgoexpwrap_" + fn.Recv.List[0].Names[0].Name() + "_" + goname
+			goname = "_cgoexpwrap_" + fn.Recv.List[0].Names[0].Name + "_" + goname
 		}
 		fmt.Fprintf(fc, "#pragma dynexport _cgoexp_%s _cgoexp_%s\n", exp.ExpName, exp.ExpName)
 		fmt.Fprintf(fc, "extern void ·%s();\n", goname)
@@ -529,23 +529,23 @@ func (p *Package) cgoType(e ast.Expr) *Type {
 				if !ok {
 					continue
 				}
-				if ts.Name.Name() == t.Name() {
+				if ts.Name.Name == t.Name {
 					return p.cgoType(ts.Type)
 				}
 			}
 		}
 		for name, def := range p.Typedef {
-			if name == t.Name() {
+			if name == t.Name {
 				return p.cgoType(def)
 			}
 		}
-		if t.Name() == "uintptr" {
+		if t.Name == "uintptr" {
 			return &Type{Size: p.PtrSize, Align: p.PtrSize, C: "uintptr"}
 		}
-		if t.Name() == "string" {
+		if t.Name == "string" {
 			return &Type{Size: p.PtrSize + 4, Align: p.PtrSize, C: "GoString"}
 		}
-		if r, ok := goTypes[t.Name()]; ok {
+		if r, ok := goTypes[t.Name]; ok {
 			if r.Align > p.PtrSize {
 				r.Align = p.PtrSize
 			}

src/cmd/godoc/godoc.go

@@ -136,11 +136,11 @@ func isPkgDir(f *os.FileInfo) bool {
 
 
 func pkgName(filename string) string {
-	file, err := parser.ParseFile(filename, nil, nil, parser.PackageClauseOnly)
+	file, err := parser.ParseFile(filename, nil, parser.PackageClauseOnly)
 	if err != nil || file == nil {
 		return ""
 	}
-	return file.Name.Name()
+	return file.Name.Name
 }
 
 
@@ -246,12 +246,12 @@ func newDirTree(path, name string, depth, maxDepth int) *Directory {
 			nfiles++
 			if synopses[0] == "" {
 				// no "optimal" package synopsis yet; continue to collect synopses
-				file, err := parser.ParseFile(pathutil.Join(path, d.Name), nil, nil,
+				file, err := parser.ParseFile(pathutil.Join(path, d.Name), nil,
 					parser.ParseComments|parser.PackageClauseOnly)
 				if err == nil && file.Doc != nil {
 					// prioritize documentation
 					i := -1
-					switch file.Name.Name() {
+					switch file.Name.Name {
 					case name:
 						i = 0 // normal case: directory name matches package name
 					case fakePkgName:
@@ -453,7 +453,7 @@ type Styler struct {
 	linetags  bool
 	highlight string
 	objmap    map[*ast.Object]int
-	count     int
+	idcount   int
 }
 
 
@@ -462,26 +462,72 @@ func newStyler(highlight string) *Styler {
 }
 
 
-func (s *Styler) id(obj *ast.Object) int {
+// identId returns a number >= 0 identifying the *ast.Object
-	n, found := s.objmap[obj]
+// denoted by name. If no object is denoted, the result is < 0.
-	if !found {
+//
-		n = s.count
+// TODO(gri): Consider making this a mapping from popup info
-		s.objmap[obj] = n
+//            (for that name) to id, instead of *ast.Object
-		s.count++
+//            to id. If a lot of the popup info is the same
+//            (e.g. type information), this will reduce the
+//            size of the html generated.
+func (s *Styler) identId(name *ast.Ident) int {
+	obj := name.Obj
+	if obj == nil || s.objmap == nil {
+		return -1
 	}
-	return n
+	id, found := s.objmap[obj]
+	if !found {
+		// first occurence
+		id = s.idcount
+		s.objmap[obj] = id
+		s.idcount++
+	}
+	return id
 }
 
 
-func (s *Styler) mapping() []*ast.Object {
+// writeObjInfo writes the popup info corresponding to obj to w.
-	if s.objmap == nil {
+// The text is HTML-escaped and does not contain single quotes.
-		return nil
+func writeObjInfo(w io.Writer, obj *ast.Object) {
+	// for now, show object kind and name; eventually
+	// do something more interesting (show declaration,
+	// for instance)
+	if obj.Kind != ast.Bad {
+		fmt.Fprintf(w, "%s ", obj.Kind)
 	}
-	m := make([]*ast.Object, s.count)
+	template.HTMLEscape(w, []byte(obj.Name))
-	for obj, i := range s.objmap {
+}
-		m[i] = obj
+
+
+// idList returns a Javascript array (source) with identifier popup
+// information: The i'th array entry is a single-quoted string with
+// the popup information for an identifier x with s.identId(x) == i,
+// for 0 <= i < s.idcount.
+func (s *Styler) idList() []byte {
+	var buf bytes.Buffer
+	fmt.Fprintln(&buf, "[")
+
+	if s.idcount > 0 {
+		// invert objmap: create an array [id]obj from map[obj]id
+		a := make([]*ast.Object, s.idcount)
+		for obj, id := range s.objmap {
+			a[id] = obj
 		}
-	return m
+
+		// for each id, print object info as single-quoted Javascript string
+		for id, obj := range a {
+			printIndex := false // enable for debugging (but longer html)
+			if printIndex {
+				fmt.Fprintf(&buf, "/* %4d */ ", id)
+			}
+			fmt.Fprint(&buf, "'")
+			writeObjInfo(&buf, obj)
+			fmt.Fprint(&buf, "',\n")
+		}
+	}
+
+	fmt.Fprintln(&buf, "]")
+	return buf.Bytes()
 }
 
 
@@ -516,13 +562,13 @@ func (s *Styler) BasicLit(x *ast.BasicLit) (text []byte, tag printer.HTMLTag) {
 }
 
 
-func (s *Styler) Ident(id *ast.Ident) (text []byte, tag printer.HTMLTag) {
+func (s *Styler) Ident(name *ast.Ident) (text []byte, tag printer.HTMLTag) {
-	text = []byte(id.Name())
+	text = []byte(name.Name)
 	var str string
-	if s.objmap != nil {
+	if id := s.identId(name); id >= 0 {
-		str = fmt.Sprintf(` id="%d"`, s.id(id.Obj))
+		str = fmt.Sprintf(` id="%d"`, id)
 	}
-	if s.highlight == id.Name() {
+	if s.highlight == name.Name {
 		str += ` class="highlight"`
 	}
 	if str != "" {
@@ -819,19 +865,6 @@ func localnameFmt(w io.Writer, x interface{}, format string) {
 }
 
 
-// Template formatter for "popupInfo" format.
-func popupInfoFmt(w io.Writer, x interface{}, format string) {
-	obj := x.(*ast.Object)
-	// for now, show object kind and name; eventually
-	// do something more interesting (show declaration,
-	// for instance)
-	if obj.Kind != ast.Err {
-		fmt.Fprintf(w, "%s ", obj.Kind)
-	}
-	template.HTMLEscape(w, []byte(obj.Name))
-}
-
-
 var fmap = template.FormatterMap{
 	"":             textFmt,
 	"html":         htmlFmt,
@@ -847,7 +880,6 @@ var fmap = template.FormatterMap{
 	"time":         timeFmt,
 	"dir/":         dirslashFmt,
 	"localname":    localnameFmt,
-	"popupInfo":    popupInfoFmt,
 }
 
 
@@ -996,22 +1028,25 @@ func applyTemplate(t *template.Template, name string, data interface{}) []byte {
 
 
 func serveGoSource(c *http.Conn, r *http.Request, abspath, relpath string) {
-	file, err := parser.ParseFile(abspath, nil, nil, parser.ParseComments)
+	file, err := parser.ParseFile(abspath, nil, parser.ParseComments)
 	if err != nil {
 		log.Stderrf("parser.ParseFile: %s", err)
 		serveError(c, r, relpath, err)
 		return
 	}
 
+	// augment AST with types; ignore errors (partial type information ok)
+	// TODO(gri): invoke typechecker
+
 	var buf bytes.Buffer
 	styler := newStyler(r.FormValue("h"))
 	writeNode(&buf, file, true, styler)
 
 	type SourceInfo struct {
+		IdList []byte
 		Source []byte
-		Data   []*ast.Object
 	}
-	info := &SourceInfo{buf.Bytes(), styler.mapping()}
+	info := &SourceInfo{styler.idList(), buf.Bytes()}
 
 	contents := applyTemplate(sourceHTML, "sourceHTML", info)
 	servePage(c, "Source file "+relpath, "", "", contents)
@@ -1346,7 +1381,7 @@ func (h *httpHandler) ServeHTTP(c *http.Conn, r *http.Request) {
 	var title string
 	switch {
 	case info.PAst != nil:
-		title = "Package " + info.PAst.Name.Name()
+		title = "Package " + info.PAst.Name.Name
 	case info.PDoc != nil:
 		switch {
 		case h.isPkg:

src/cmd/godoc/index.go

@@ -452,10 +452,10 @@ func (x *Indexer) visitComment(c *ast.CommentGroup) {
 
 func (x *Indexer) visitIdent(kind SpotKind, id *ast.Ident) {
 	if id != nil {
-		lists, found := x.words[id.Name()]
+		lists, found := x.words[id.Name]
 		if !found {
 			lists = new(IndexResult)
-			x.words[id.Name()] = lists
+			x.words[id.Name] = lists
 		}
 
 		if kind == Use || x.decl == nil {
@@ -596,13 +596,13 @@ func (x *Indexer) VisitFile(path string, f *os.FileInfo) {
 		return
 	}
 
-	file, err := parser.ParseFile(path, nil, nil, parser.ParseComments)
+	file, err := parser.ParseFile(path, nil, parser.ParseComments)
 	if err != nil {
 		return // ignore files with (parse) errors
 	}
 
 	dir, _ := pathutil.Split(path)
-	pak := Pak{dir, file.Name.Name()}
+	pak := Pak{dir, file.Name.Name}
 	x.file = &File{path, pak}
 	ast.Walk(x, file)
 }

src/cmd/godoc/snippet.go

@@ -35,7 +35,7 @@ func (s *snippetStyler) LineTag(line int) (text []uint8, tag printer.HTMLTag) {
 
 
 func (s *snippetStyler) Ident(id *ast.Ident) (text []byte, tag printer.HTMLTag) {
-	text = []byte(id.Name())
+	text = []byte(id.Name)
 	if s.highlight == id {
 		tag = printer.HTMLTag{"<span class=highlight>", "</span>"}
 	}
@@ -114,7 +114,7 @@ func NewSnippet(decl ast.Decl, id *ast.Ident) (s *Snippet) {
 	if s == nil {
 		s = &Snippet{
 			id.Pos().Line,
-			fmt.Sprintf(`could not generate a snippet for <span class="highlight">%s</span>`, id.Name()),
+			fmt.Sprintf(`could not generate a snippet for <span class="highlight">%s</span>`, id.Name),
 		}
 	}
 	return

src/cmd/gofmt/gofmt.go

@@ -27,7 +27,6 @@ var (
 
 	// debugging support
 	comments = flag.Bool("comments", true, "print comments")
-	debug    = flag.Bool("debug", false, "print debugging information")
 	trace    = flag.Bool("trace", false, "print parse trace")
 
 	// layout control
@@ -92,11 +91,7 @@ func processFile(f *os.File) os.Error {
 		return err
 	}
 
-	var scope *ast.Scope
+	file, err := parser.ParseFile(f.Name(), src, parserMode)
-	if *debug {
-		scope = ast.NewScope(nil)
-	}
-	file, err := parser.ParseFile(f.Name(), src, scope, parserMode)
 
 	if err != nil {
 		return err

src/cmd/gofmt/rewrite.go

@@ -37,7 +37,7 @@ func initRewrite() {
 // but there are problems with preserving formatting and also
 // with what a wildcard for a statement looks like.
 func parseExpr(s string, what string) ast.Expr {
-	x, err := parser.ParseExpr("input", s, nil)
+	x, err := parser.ParseExpr("input", s)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "parsing %s %s: %s\n", what, s, err)
 		os.Exit(2)
@@ -109,7 +109,7 @@ func match(m map[string]reflect.Value, pattern, val reflect.Value) bool {
 	// times in the pattern, it must match the same expression
 	// each time.
 	if m != nil && pattern.Type() == identType {
-		name := pattern.Interface().(*ast.Ident).Name()
+		name := pattern.Interface().(*ast.Ident).Name
 		if isWildcard(name) {
 			if old, ok := m[name]; ok {
 				return match(nil, old, val)
@@ -139,7 +139,7 @@ func match(m map[string]reflect.Value, pattern, val reflect.Value) bool {
 		// of recursing down any further via reflection.
 		p := pattern.Interface().(*ast.Ident)
 		v := val.Interface().(*ast.Ident)
-		return p == nil && v == nil || p != nil && v != nil && p.Name() == v.Name()
+		return p == nil && v == nil || p != nil && v != nil && p.Name == v.Name
 	}
 
 	p := reflect.Indirect(pattern)
@@ -194,7 +194,7 @@ func subst(m map[string]reflect.Value, pattern reflect.Value, pos reflect.Value)
 
 	// Wildcard gets replaced with map value.
 	if m != nil && pattern.Type() == identType {
-		name := pattern.Interface().(*ast.Ident).Name()
+		name := pattern.Interface().(*ast.Ident).Name
 		if isWildcard(name) {
 			if old, ok := m[name]; ok {
 				return subst(nil, old, nil)

src/cmd/goinstall/parse.go

@@ -41,11 +41,11 @@ func goFiles(dir string, allowMain bool) (files []string, imports map[string]str
 			continue
 		}
 		filename := path.Join(dir, d.Name)
-		pf, err := parser.ParseFile(filename, nil, nil, parser.ImportsOnly)
+		pf, err := parser.ParseFile(filename, nil, parser.ImportsOnly)
 		if err != nil {
 			return nil, nil, "", err
 		}
-		s := string(pf.Name.Name())
+		s := string(pf.Name.Name)
 		if s == "main" && !allowMain {
 			continue
 		}

src/pkg/exp/eval/expr.go

@@ -585,7 +585,7 @@ func (a *exprCompiler) compile(x ast.Expr, callCtx bool) *expr {
 		}
 
 	case *ast.Ident:
-		return ei.compileIdent(a.block, a.constant, callCtx, x.Name())
+		return ei.compileIdent(a.block, a.constant, callCtx, x.Name)
 
 	case *ast.IndexExpr:
 		l, r := a.compile(x.X, false), a.compile(x.Index, false)
@@ -621,7 +621,7 @@ func (a *exprCompiler) compile(x ast.Expr, callCtx bool) *expr {
 		if v == nil {
 			return nil
 		}
-		return ei.compileSelectorExpr(v, x.Sel.Name())
+		return ei.compileSelectorExpr(v, x.Sel.Name)
 
 	case *ast.StarExpr:
 		// We pass down our call context because this could be

src/pkg/exp/eval/stmt.go

@@ -210,15 +210,15 @@ func (f *flowBuf) gotosObeyScopes(a *compiler) {
  */
 
 func (a *stmtCompiler) defineVar(ident *ast.Ident, t Type) *Variable {
-	v, prev := a.block.DefineVar(ident.Name(), ident.Pos(), t)
+	v, prev := a.block.DefineVar(ident.Name, ident.Pos(), t)
 	if prev != nil {
 		// TODO(austin) It's silly that we have to capture
 		// Pos() in a variable.
 		pos := prev.Pos()
 		if pos.IsValid() {
-			a.diagAt(ident, "variable %s redeclared in this block\n\tprevious declaration at %s", ident.Name(), &pos)
+			a.diagAt(ident, "variable %s redeclared in this block\n\tprevious declaration at %s", ident.Name, &pos)
 		} else {
-			a.diagAt(ident, "variable %s redeclared in this block", ident.Name())
+			a.diagAt(ident, "variable %s redeclared in this block", ident.Name)
 		}
 		return nil
 	}
@@ -381,13 +381,13 @@ func (a *stmtCompiler) compileDecl(decl ast.Decl) {
 		}
 		// Declare and initialize v before compiling func
 		// so that body can refer to itself.
-		c, prev := a.block.DefineConst(d.Name.Name(), a.pos, decl.Type, decl.Type.Zero())
+		c, prev := a.block.DefineConst(d.Name.Name, a.pos, decl.Type, decl.Type.Zero())
 		if prev != nil {
 			pos := prev.Pos()
 			if pos.IsValid() {
-				a.diagAt(d.Name, "identifier %s redeclared in this block\n\tprevious declaration at %s", d.Name.Name(), &pos)
+				a.diagAt(d.Name, "identifier %s redeclared in this block\n\tprevious declaration at %s", d.Name.Name, &pos)
 			} else {
-				a.diagAt(d.Name, "identifier %s redeclared in this block", d.Name.Name())
+				a.diagAt(d.Name, "identifier %s redeclared in this block", d.Name.Name)
 			}
 		}
 		fn := a.compileFunc(a.block, decl, d.Body)
@@ -416,14 +416,14 @@ func (a *stmtCompiler) compileDecl(decl ast.Decl) {
 
 func (a *stmtCompiler) compileLabeledStmt(s *ast.LabeledStmt) {
 	// Define label
-	l, ok := a.labels[s.Label.Name()]
+	l, ok := a.labels[s.Label.Name]
 	if ok {
 		if l.resolved.IsValid() {
-			a.diag("label %s redeclared in this block\n\tprevious declaration at %s", s.Label.Name(), &l.resolved)
+			a.diag("label %s redeclared in this block\n\tprevious declaration at %s", s.Label.Name, &l.resolved)
 		}
 	} else {
 		pc := badPC
-		l = &label{name: s.Label.Name(), gotoPC: &pc}
+		l = &label{name: s.Label.Name, gotoPC: &pc}
 		a.labels[l.name] = l
 	}
 	l.desc = "regular label"
@@ -562,7 +562,7 @@ func (a *stmtCompiler) doAssign(lhs []ast.Expr, rhs []ast.Expr, tok token.Token,
 			}
 
 			// Is this simply an assignment?
-			if _, ok := a.block.defs[ident.Name()]; ok {
+			if _, ok := a.block.defs[ident.Name]; ok {
 				ident = nil
 				break
 			}
@@ -861,7 +861,7 @@ func (a *stmtCompiler) findLexicalLabel(name *ast.Ident, pred func(*label) bool,
 		if name == nil && pred(l) {
 			return l
 		}
-		if name != nil && l.name == name.Name() {
+		if name != nil && l.name == name.Name {
 			if !pred(l) {
 				a.diag("cannot %s to %s %s", errOp, l.desc, l.name)
 				return nil
@@ -872,7 +872,7 @@ func (a *stmtCompiler) findLexicalLabel(name *ast.Ident, pred func(*label) bool,
 	if name == nil {
 		a.diag("%s outside %s", errOp, errCtx)
 	} else {
-		a.diag("%s label %s not defined", errOp, name.Name())
+		a.diag("%s label %s not defined", errOp, name.Name)
 	}
 	return nil
 }
@@ -896,10 +896,10 @@ func (a *stmtCompiler) compileBranchStmt(s *ast.BranchStmt) {
 		pc = l.continuePC
 
 	case token.GOTO:
-		l, ok := a.labels[s.Label.Name()]
+		l, ok := a.labels[s.Label.Name]
 		if !ok {
 			pc := badPC
-			l = &label{name: s.Label.Name(), desc: "unresolved label", gotoPC: &pc, used: s.Pos()}
+			l = &label{name: s.Label.Name, desc: "unresolved label", gotoPC: &pc, used: s.Pos()}
 			a.labels[l.name] = l
 		}
 
@@ -1235,14 +1235,14 @@ func (a *compiler) compileFunc(b *block, decl *FuncDecl, body *ast.BlockStmt) fu
 	defer bodyScope.exit()
 	for i, t := range decl.Type.In {
 		if decl.InNames[i] != nil {
-			bodyScope.DefineVar(decl.InNames[i].Name(), decl.InNames[i].Pos(), t)
+			bodyScope.DefineVar(decl.InNames[i].Name, decl.InNames[i].Pos(), t)
 		} else {
 			bodyScope.DefineTemp(t)
 		}
 	}
 	for i, t := range decl.Type.Out {
 		if decl.OutNames[i] != nil {
-			bodyScope.DefineVar(decl.OutNames[i].Name(), decl.OutNames[i].Pos(), t)
+			bodyScope.DefineVar(decl.OutNames[i].Name, decl.OutNames[i].Pos(), t)
 		} else {
 			bodyScope.DefineTemp(t)
 		}

src/pkg/exp/eval/type.go

@@ -771,7 +771,7 @@ func typeListString(ts []Type, ns []*ast.Ident) string {
 			s += ", "
 		}
 		if ns != nil && ns[i] != nil {
-			s += ns[i].Name() + " "
+			s += ns[i].Name + " "
 		}
 		if t == nil {
 			// Some places use nil types to represent errors
@@ -815,7 +815,7 @@ type FuncDecl struct {
 func (t *FuncDecl) String() string {
 	s := "func"
 	if t.Name != nil {
-		s += " " + t.Name.Name()
+		s += " " + t.Name.Name
 	}
 	s += funcTypeString(t.Type, t.InNames, t.OutNames)
 	return s

src/pkg/exp/eval/typec.go

@@ -26,17 +26,17 @@ type typeCompiler struct {
 }
 
 func (a *typeCompiler) compileIdent(x *ast.Ident, allowRec bool) Type {
-	_, _, def := a.block.Lookup(x.Name())
+	_, _, def := a.block.Lookup(x.Name)
 	if def == nil {
-		a.diagAt(x, "%s: undefined", x.Name())
+		a.diagAt(x, "%s: undefined", x.Name)
 		return nil
 	}
 	switch def := def.(type) {
 	case *Constant:
-		a.diagAt(x, "constant %v used as type", x.Name())
+		a.diagAt(x, "constant %v used as type", x.Name)
 		return nil
 	case *Variable:
-		a.diagAt(x, "variable %v used as type", x.Name())
+		a.diagAt(x, "variable %v used as type", x.Name)
 		return nil
 	case *NamedType:
 		if !allowRec && def.incomplete {
@@ -51,7 +51,7 @@ func (a *typeCompiler) compileIdent(x *ast.Ident, allowRec bool) Type {
 	case Type:
 		return def
 	}
-	log.Crashf("name %s has unknown type %T", x.Name(), def)
+	log.Crashf("name %s has unknown type %T", x.Name, def)
 	return nil
 }
 
@@ -137,7 +137,7 @@ func (a *typeCompiler) compileStructType(x *ast.StructType, allowRec bool) Type
 		// Compute field name and check anonymous fields
 		var name string
 		if names[i] != nil {
-			name = names[i].Name()
+			name = names[i].Name
 		} else {
 			if ts[i] == nil {
 				continue
@@ -237,7 +237,7 @@ func (a *typeCompiler) compileInterfaceType(x *ast.InterfaceType, allowRec bool)
 		}
 
 		if names[i] != nil {
-			name := names[i].Name()
+			name := names[i].Name
 			methods[nm].Name = name
 			methods[nm].Type = ts[i].(*FuncType)
 			nm++
@@ -370,7 +370,7 @@ func (a *compiler) compileTypeDecl(b *block, decl *ast.GenDecl) bool {
 	for _, spec := range decl.Specs {
 		spec := spec.(*ast.TypeSpec)
 		// Create incomplete type for this type
-		nt := b.DefineType(spec.Name.Name(), spec.Name.Pos(), nil)
+		nt := b.DefineType(spec.Name.Name, spec.Name.Pos(), nil)
 		if nt != nil {
 			nt.(*NamedType).incomplete = true
 		}

src/pkg/exp/eval/world.go

@@ -136,13 +136,13 @@ func (e *exprCode) Run() (Value, os.Error) {
 }
 
 func (w *World) Compile(text string) (Code, os.Error) {
-	stmts, err := parser.ParseStmtList("input", text, nil)
+	stmts, err := parser.ParseStmtList("input", text)
 	if err == nil {
 		return w.CompileStmtList(stmts)
 	}
 
 	// Otherwise try as DeclList.
-	decls, err1 := parser.ParseDeclList("input", text, nil)
+	decls, err1 := parser.ParseDeclList("input", text)
 	if err1 == nil {
 		return w.CompileDeclList(decls)
 	}

src/pkg/go/ast/ast.go

@@ -141,7 +141,8 @@ type (
 	// An Ident node represents an identifier.
 	Ident struct {
 		token.Position         // identifier position
-		Obj            *Object // denoted object
+		Name           string  // identifier name
+		Obj            *Object // denoted object; or nil
 	}
 
 	// An Ellipsis node stands for the "..." type in a
@@ -156,7 +157,7 @@ type (
 	BasicLit struct {
 		token.Position             // literal position
 		Kind           token.Token // token.INT, token.FLOAT, token.IMAG, token.CHAR, or token.STRING
-		Value          []byte      // literal string; e.g. 42, 0x7f, 3.14, 1e-9, 'a', '\x7f', "foo" or `\m\n\o`
+		Value          []byte      // literal string; e.g. 42, 0x7f, 3.14, 1e-9, 2.4i, 'a', '\x7f', "foo" or `\m\n\o`
 	}
 
 	// A FuncLit node represents a function literal.
@@ -166,7 +167,6 @@ type (
 	}
 
 	// A CompositeLit node represents a composite literal.
-	//
 	CompositeLit struct {
 		Type   Expr           // literal type
 		Lbrace token.Position // position of "{"
@@ -218,6 +218,7 @@ type (
 
 	// A StarExpr node represents an expression of the form "*" Expression.
 	// Semantically it could be a unary "*" expression, or a pointer type.
+	//
 	StarExpr struct {
 		token.Position      // position of "*"
 		X              Expr // operand
@@ -233,7 +234,6 @@ type (
 	}
 
 	// A BinaryExpr node represents a binary expression.
-	//
 	BinaryExpr struct {
 		X     Expr           // left operand
 		OpPos token.Position // position of Op
@@ -330,6 +330,7 @@ func (x *KeyValueExpr) Pos() token.Position   { return x.Key.Pos() }
 
 // exprNode() ensures that only expression/type nodes can be
 // assigned to an ExprNode.
+//
 func (x *BadExpr) exprNode()        {}
 func (x *Ident) exprNode()          {}
 func (x *Ellipsis) exprNode()       {}
@@ -360,15 +361,15 @@ func (x *ChanType) exprNode()      {}
 
 var noPos token.Position
 
-// NewIdent creates a new Ident without position and minimal object
+// NewIdent creates a new Ident without position.
-// information. Useful for ASTs generated by code other than the Go
+// Useful for ASTs generated by code other than the Go parser.
-// parser.
 //
-func NewIdent(name string) *Ident { return &Ident{noPos, NewObj(Err, noPos, name)} }
+func NewIdent(name string) *Ident { return &Ident{noPos, name, nil} }
 
 
 // IsExported returns whether name is an exported Go symbol
 // (i.e., whether it begins with an uppercase letter).
+//
 func IsExported(name string) bool {
 	ch, _ := utf8.DecodeRuneInString(name)
 	return unicode.IsUpper(ch)
@@ -377,16 +378,13 @@ func IsExported(name string) bool {
 
 // IsExported returns whether id is an exported Go symbol
 // (i.e., whether it begins with an uppercase letter).
-func (id *Ident) IsExported() bool { return id.Obj.IsExported() }
+//
-
+func (id *Ident) IsExported() bool { return IsExported(id.Name) }
-
-// Name returns an identifier's name.
-func (id *Ident) Name() string { return id.Obj.Name }
 
 
 func (id *Ident) String() string {
-	if id != nil && id.Obj != nil {
+	if id != nil {
-		return id.Obj.Name
+		return id.Name
 	}
 	return "<nil>"
 }
@@ -441,6 +439,7 @@ type (
 
 	// An AssignStmt node represents an assignment or
 	// a short variable declaration.
+	//
 	AssignStmt struct {
 		Lhs    []Expr
 		TokPos token.Position // position of Tok
@@ -618,6 +617,7 @@ type (
 
 	// A ValueSpec node represents a constant or variable declaration
 	// (ConstSpec or VarSpec production).
+	//
 	ValueSpec struct {
 		Doc     *CommentGroup // associated documentation; or nil
 		Names   []*Ident      // value names
@@ -630,7 +630,7 @@ type (
 	TypeSpec struct {
 		Doc     *CommentGroup // associated documentation; or nil
 		Name    *Ident        // type name
-		Type    Expr          // *ArrayType, *StructType, *FuncType, *InterfaceType, *MapType, *ChanType or *Ident
+		Type    Expr          // *Ident, *ParenExpr, *SelectorExpr, *StarExpr, or any of the *XxxTypes
 		Comment *CommentGroup // line comments; or nil
 	}
 )
@@ -734,6 +734,6 @@ type File struct {
 //
 type Package struct {
 	Name  string           // package name
-	Scope *Scope           // package scope
+	Scope *Scope           // package scope; or nil
 	Files map[string]*File // Go source files by filename
 }

src/pkg/go/ast/filter.go

@@ -197,7 +197,7 @@ type Filter func(string) bool
 func filterIdentList(list []*Ident, f Filter) []*Ident {
 	j := 0
 	for _, x := range list {
-		if f(x.Name()) {
+		if f(x.Name) {
 			list[j] = x
 			j++
 		}
@@ -212,7 +212,7 @@ func filterSpec(spec Spec, f Filter) bool {
 		s.Names = filterIdentList(s.Names, f)
 		return len(s.Names) > 0
 	case *TypeSpec:
-		return f(s.Name.Name())
+		return f(s.Name.Name)
 	}
 	return false
 }
@@ -236,7 +236,7 @@ func filterDecl(decl Decl, f Filter) bool {
 		d.Specs = filterSpecList(d.Specs, f)
 		return len(d.Specs) > 0
 	case *FuncDecl:
-		return f(d.Name.Name())
+		return f(d.Name.Name)
 	}
 	return false
 }
@@ -397,7 +397,7 @@ func MergePackageFiles(pkg *Package, mode MergeMode) *File {
 					//            entities (const, type, vars) if
 					//            multiple declarations are common.
 					if f, isFun := d.(*FuncDecl); isFun {
-						name := f.Name.Name()
+						name := f.Name.Name
 						if j, exists := funcs[name]; exists {
 							// function declared already
 							if decls[j] != nil && decls[j].(*FuncDecl).Doc == nil {

src/pkg/go/ast/scope.go

@@ -4,13 +4,11 @@
 
 package ast
 
-import "go/token"
-
 type ObjKind int
 
 // The list of possible Object kinds.
 const (
-	Err ObjKind = iota // object kind unknown (forward reference or error)
+	Bad ObjKind = iota // bad object
 	Pkg                // package
 	Con                // constant
 	Typ                // type
@@ -20,7 +18,7 @@ const (
 
 
 var objKindStrings = [...]string{
-	Err: "<unknown object kind>",
+	Bad: "bad",
 	Pkg: "package",
 	Con: "const",
 	Typ: "type",
@@ -37,13 +35,13 @@ func (kind ObjKind) String() string { return objKindStrings[kind] }
 //
 type Object struct {
 	Kind ObjKind
-	Pos  token.Position // declaration position
 	Name string      // declared name
+	Decl interface{} // corresponding Field, xxxSpec or FuncDecl
 }
 
 
-func NewObj(kind ObjKind, pos token.Position, name string) *Object {
+func NewObj(kind ObjKind, name string) *Object {
-	return &Object{kind, pos, name}
+	return &Object{kind, name, nil}
 }
 
 
@@ -57,12 +55,43 @@ func (obj *Object) IsExported() bool { return IsExported(obj.Name) }
 //
 type Scope struct {
 	Outer   *Scope
-	Objects map[string]*Object
+	Objects []*Object // in declaration order
+	// Implementation note: In some cases (struct fields,
+	// function parameters) we need the source order of
+	// variables. Thus for now, we store scope entries
+	// in a linear list. If scopes become very large
+	// (say, for packages), we may need to change this
+	// to avoid slow lookups.
 }
 
 
 // NewScope creates a new scope nested in the outer scope.
-func NewScope(outer *Scope) *Scope { return &Scope{outer, make(map[string]*Object)} }
+func NewScope(outer *Scope) *Scope {
+	const n = 4 // initial scope capacity, must be > 0
+	return &Scope{outer, make([]*Object, 0, n)}
+}
+
+
+func (s *Scope) append(obj *Object) {
+	n := len(s.Objects)
+	if n >= cap(s.Objects) {
+		new := make([]*Object, 2*n)
+		copy(new, s.Objects)
+		s.Objects = new
+	}
+	s.Objects = s.Objects[0 : n+1]
+	s.Objects[n] = obj
+}
+
+
+func (s *Scope) lookup(name string) *Object {
+	for _, obj := range s.Objects {
+		if obj.Name == name {
+			return obj
+		}
+	}
+	return nil
+}
 
 
 // Declare attempts to insert a named object into the scope s.
@@ -71,12 +100,12 @@ func NewScope(outer *Scope) *Scope { return &Scope{outer, make(map[string]*Objec
 // scope remains unchanged and Declare returns the object found
 // in the scope instead.
 func (s *Scope) Declare(obj *Object) *Object {
-	decl, found := s.Objects[obj.Name]
+	alt := s.lookup(obj.Name)
-	if !found {
+	if alt == nil {
-		s.Objects[obj.Name] = obj
+		s.append(obj)
-		decl = obj
+		alt = obj
 	}
-	return decl
+	return alt
 }
 
 
@@ -85,7 +114,7 @@ func (s *Scope) Declare(obj *Object) *Object {
 //
 func (s *Scope) Lookup(name string) *Object {
 	for ; s != nil; s = s.Outer {
-		if obj, found := s.Objects[name]; found {
+		if obj := s.lookup(name); obj != nil {
 			return obj
 		}
 	}

src/pkg/go/doc/doc.go

@@ -77,7 +77,7 @@ func (doc *docReader) addDoc(comments *ast.CommentGroup) {
 
 func (doc *docReader) addType(decl *ast.GenDecl) {
 	spec := decl.Specs[0].(*ast.TypeSpec)
-	typ := doc.lookupTypeDoc(spec.Name.Name())
+	typ := doc.lookupTypeDoc(spec.Name.Name)
 	// typ should always be != nil since declared types
 	// are always named - be conservative and check
 	if typ != nil {
@@ -108,7 +108,7 @@ func baseTypeName(typ ast.Expr) string {
 		// if the type is not exported, the effect to
 		// a client is as if there were no type name
 		if t.IsExported() {
-			return string(t.Name())
+			return string(t.Name)
 		}
 	case *ast.StarExpr:
 		return baseTypeName(t.X)
@@ -173,7 +173,7 @@ func (doc *docReader) addValue(decl *ast.GenDecl) {
 // at least one f with associated documentation is stored in table, if there
 // are multiple f's with the same name.
 func setFunc(table map[string]*ast.FuncDecl, f *ast.FuncDecl) {
-	name := f.Name.Name()
+	name := f.Name.Name
 	if g, exists := table[name]; exists && g.Doc != nil {
 		// a function with the same name has already been registered;
 		// since it has documentation, assume f is simply another
@@ -188,7 +188,7 @@ func setFunc(table map[string]*ast.FuncDecl, f *ast.FuncDecl) {
 
 
 func (doc *docReader) addFunc(fun *ast.FuncDecl) {
-	name := fun.Name.Name()
+	name := fun.Name.Name
 
 	// determine if it should be associated with a type
 	if fun.Recv != nil {
@@ -325,7 +325,7 @@ func (doc *docReader) addFile(src *ast.File) {
 
 func NewFileDoc(file *ast.File) *PackageDoc {
 	var r docReader
-	r.init(file.Name.Name())
+	r.init(file.Name.Name)
 	r.addFile(file)
 	return r.newDoc("", nil)
 }
@@ -370,9 +370,9 @@ func declName(d *ast.GenDecl) string {
 
 	switch v := d.Specs[0].(type) {
 	case *ast.ValueSpec:
-		return v.Names[0].Name()
+		return v.Names[0].Name
 	case *ast.TypeSpec:
-		return v.Name.Name()
+		return v.Name.Name
 	}
 
 	return ""
@@ -434,7 +434,7 @@ func makeFuncDocs(m map[string]*ast.FuncDecl) []*FuncDoc {
 		if f.Recv != nil {
 			doc.Recv = f.Recv.List[0].Type
 		}
-		doc.Name = f.Name.Name()
+		doc.Name = f.Name.Name
 		doc.Decl = f
 		d[i] = doc
 		i++
@@ -467,7 +467,7 @@ func (p sortTypeDoc) Less(i, j int) bool {
 	// sort by name
 	// pull blocks (name = "") up to top
 	// in original order
-	if ni, nj := p[i].Type.Name.Name(), p[j].Type.Name.Name(); ni != nj {
+	if ni, nj := p[i].Type.Name.Name, p[j].Type.Name.Name; ni != nj {
 		return ni < nj
 	}
 	return p[i].order < p[j].order
@@ -587,12 +587,12 @@ func matchDecl(d *ast.GenDecl, f Filter) bool {
 		switch v := d.(type) {
 		case *ast.ValueSpec:
 			for _, name := range v.Names {
-				if f(name.Name()) {
+				if f(name.Name) {
 					return true
 				}
 			}
 		case *ast.TypeSpec:
-			if f(v.Name.Name()) {
+			if f(v.Name.Name) {
 				return true
 			}
 		}

src/pkg/go/parser/interface.go

@@ -57,52 +57,52 @@ func (p *parser) parseEOF() os.Error {
 
 
 // ParseExpr parses a Go expression and returns the corresponding
-// AST node. The filename, src, and scope arguments have the same interpretation
+// AST node. The filename and src arguments have the same interpretation
 // as for ParseFile. If there is an error, the result expression
 // may be nil or contain a partial AST.
 //
-func ParseExpr(filename string, src interface{}, scope *ast.Scope) (ast.Expr, os.Error) {
+func ParseExpr(filename string, src interface{}) (ast.Expr, os.Error) {
 	data, err := readSource(filename, src)
 	if err != nil {
 		return nil, err
 	}
 
 	var p parser
-	p.init(filename, data, scope, 0)
+	p.init(filename, data, 0)
 	return p.parseExpr(), p.parseEOF()
 }
 
 
 // ParseStmtList parses a list of Go statements and returns the list
-// of corresponding AST nodes. The filename, src, and scope arguments have the same
+// of corresponding AST nodes. The filename and src arguments have the same
 // interpretation as for ParseFile. If there is an error, the node
 // list may be nil or contain partial ASTs.
 //
-func ParseStmtList(filename string, src interface{}, scope *ast.Scope) ([]ast.Stmt, os.Error) {
+func ParseStmtList(filename string, src interface{}) ([]ast.Stmt, os.Error) {
 	data, err := readSource(filename, src)
 	if err != nil {
 		return nil, err
 	}
 
 	var p parser
-	p.init(filename, data, scope, 0)
+	p.init(filename, data, 0)
 	return p.parseStmtList(), p.parseEOF()
 }
 
 
 // ParseDeclList parses a list of Go declarations and returns the list
-// of corresponding AST nodes.  The filename, src, and scope arguments have the same
+// of corresponding AST nodes.  The filename and src arguments have the same
 // interpretation as for ParseFile. If there is an error, the node
 // list may be nil or contain partial ASTs.
 //
-func ParseDeclList(filename string, src interface{}, scope *ast.Scope) ([]ast.Decl, os.Error) {
+func ParseDeclList(filename string, src interface{}) ([]ast.Decl, os.Error) {
 	data, err := readSource(filename, src)
 	if err != nil {
 		return nil, err
 	}
 
 	var p parser
-	p.init(filename, data, scope, 0)
+	p.init(filename, data, 0)
 	return p.parseDeclList(), p.parseEOF()
 }
 
@@ -116,11 +116,6 @@ func ParseDeclList(filename string, src interface{}, scope *ast.Scope) ([]ast.De
 //
 // If src == nil, ParseFile parses the file specified by filename.
 //
-// If scope != nil, it is the immediately surrounding scope for the file
-// (the package scope) and it is used to lookup and declare identifiers.
-// When parsing multiple files belonging to a package, the same scope should
-// be provided to all files.
-//
 // The mode parameter controls the amount of source text parsed and other
 // optional parser functionality.
 //
@@ -130,14 +125,14 @@ func ParseDeclList(filename string, src interface{}, scope *ast.Scope) ([]ast.De
 // representing the fragments of erroneous source code). Multiple errors
 // are returned via a scanner.ErrorList which is sorted by file position.
 //
-func ParseFile(filename string, src interface{}, scope *ast.Scope, mode uint) (*ast.File, os.Error) {
+func ParseFile(filename string, src interface{}, mode uint) (*ast.File, os.Error) {
 	data, err := readSource(filename, src)
 	if err != nil {
 		return nil, err
 	}
 
 	var p parser
-	p.init(filename, data, scope, mode)
+	p.init(filename, data, mode)
 	return p.parseFile(), p.GetError(scanner.NoMultiples) // parseFile() reads to EOF
 }
 
@@ -150,14 +145,14 @@ func ParseFile(filename string, src interface{}, scope *ast.Scope, mode uint) (*
 // be incomplete (missing packages and/or incomplete packages) and the first
 // error encountered is returned.
 //
-func ParseFiles(filenames []string, scope *ast.Scope, mode uint) (pkgs map[string]*ast.Package, first os.Error) {
+func ParseFiles(filenames []string, mode uint) (pkgs map[string]*ast.Package, first os.Error) {
 	pkgs = make(map[string]*ast.Package)
 	for _, filename := range filenames {
-		if src, err := ParseFile(filename, nil, scope, mode); err == nil {
+		if src, err := ParseFile(filename, nil, mode); err == nil {
-			name := src.Name.Name()
+			name := src.Name.Name
 			pkg, found := pkgs[name]
 			if !found {
-				pkg = &ast.Package{name, scope, make(map[string]*ast.File)}
+				pkg = &ast.Package{name, nil, make(map[string]*ast.File)}
 				pkgs[name] = pkg
 			}
 			pkg.Files[filename] = src
@@ -201,6 +196,5 @@ func ParseDir(path string, filter func(*os.FileInfo) bool, mode uint) (map[strin
 	}
 	filenames = filenames[0:n]
 
-	var scope *ast.Scope = nil // for now tracking of declarations is disabled
+	return ParseFiles(filenames, mode)
-	return ParseFiles(filenames, scope, mode)
 }

src/pkg/go/parser/parser.go

@@ -56,12 +56,6 @@ type parser struct {
 
 	// Non-syntactic parser control
 	exprLev int // < 0: in control clause, >= 0: in expression
-
-	// Scopes
-	checkDecl bool // if set, check declarations
-	pkgScope  *ast.Scope
-	fileScope *ast.Scope
-	funcScope *ast.Scope
 }
 
 
@@ -75,16 +69,10 @@ func scannerMode(mode uint) uint {
 }
 
 
-func (p *parser) init(filename string, src []byte, scope *ast.Scope, mode uint) {
+func (p *parser) init(filename string, src []byte, mode uint) {
 	p.scanner.Init(filename, src, p, scannerMode(mode))
 	p.mode = mode
 	p.trace = mode&Trace != 0 // for convenience (p.trace is used frequently)
-	if scope != nil {
-		p.checkDecl = true
-	} else {
-		scope = ast.NewScope(nil) // provide a dummy scope
-	}
-	p.pkgScope = scope
 	p.next()
 }
 
@@ -276,39 +264,31 @@ func (p *parser) expectSemi() {
 
 
 // ----------------------------------------------------------------------------
-// Scope support
+// Identifiers
 
-func (p *parser) openScope() *ast.Scope {
+func (p *parser) parseIdent() *ast.Ident {
-	p.funcScope = ast.NewScope(p.funcScope)
+	pos := p.pos
-	return p.funcScope
+	name := "_"
-}
-
-
-func (p *parser) closeScope() { p.funcScope = p.funcScope.Outer }
-
-
-func (p *parser) parseIdent(kind ast.ObjKind) *ast.Ident {
-	obj := ast.NewObj(kind, p.pos, "_")
 	if p.tok == token.IDENT {
-		obj.Name = string(p.lit)
+		name = string(p.lit)
 		p.next()
 	} else {
 		p.expect(token.IDENT) // use expect() error handling
 	}
-	return &ast.Ident{obj.Pos, obj}
+	return &ast.Ident{pos, name, nil}
 }
 
 
-func (p *parser) parseIdentList(kind ast.ObjKind) []*ast.Ident {
+func (p *parser) parseIdentList() []*ast.Ident {
 	if p.trace {
 		defer un(trace(p, "IdentList"))
 	}
 
 	var list vector.Vector
-	list.Push(p.parseIdent(kind))
+	list.Push(p.parseIdent())
 	for p.tok == token.COMMA {
 		p.next()
-		list.Push(p.parseIdent(kind))
+		list.Push(p.parseIdent())
 	}
 
 	// convert vector
@@ -321,82 +301,6 @@ func (p *parser) parseIdentList(kind ast.ObjKind) []*ast.Ident {
 }
 
 
-func (p *parser) declIdent(scope *ast.Scope, id *ast.Ident) {
-	decl := scope.Declare(id.Obj)
-	if p.checkDecl && decl != id.Obj {
-		if decl.Kind == ast.Err {
-			// declared object is a forward declaration - update it
-			*decl = *id.Obj
-			id.Obj = decl
-			return
-		}
-		p.Error(id.Pos(), "'"+id.Name()+"' declared already at "+decl.Pos.String())
-	}
-}
-
-
-func (p *parser) declIdentList(scope *ast.Scope, list []*ast.Ident) {
-	for _, id := range list {
-		p.declIdent(scope, id)
-	}
-}
-
-
-func (p *parser) declFieldList(scope *ast.Scope, list []*ast.Field) {
-	for _, f := range list {
-		p.declIdentList(scope, f.Names)
-	}
-}
-
-
-func (p *parser) findIdent() *ast.Ident {
-	pos := p.pos
-	name := "_"
-	var obj *ast.Object
-	if p.tok == token.IDENT {
-		name = string(p.lit)
-		obj = p.funcScope.Lookup(name)
-		p.next()
-	} else {
-		p.expect(token.IDENT) // use expect() error handling
-	}
-	if obj == nil {
-		// No declaration found: either we are outside any function
-		// (p.funcScope == nil) or the identifier is not declared
-		// in any function. Try the file and package scope.
-		obj = p.fileScope.Lookup(name) // file scope is nested in package scope
-		if obj == nil {
-			// No declaration found anywhere: track as
-			// unresolved identifier in the package scope.
-			obj = ast.NewObj(ast.Err, pos, name)
-			p.pkgScope.Declare(obj)
-		}
-	}
-	return &ast.Ident{pos, obj}
-}
-
-
-func (p *parser) findIdentInScope(scope *ast.Scope) *ast.Ident {
-	pos := p.pos
-	name := "_"
-	var obj *ast.Object
-	if p.tok == token.IDENT {
-		name = string(p.lit)
-		obj = scope.Lookup(name)
-		p.next()
-	} else {
-		p.expect(token.IDENT) // use expect() error handling
-	}
-	if obj == nil {
-		// TODO(gri) At the moment we always arrive here because
-		//           we don't track the lookup scope (and sometimes
-		//           we can't). Just create a useable ident for now.
-		obj = ast.NewObj(ast.Err, pos, name)
-	}
-	return &ast.Ident{pos, obj}
-}
-
-
 // ----------------------------------------------------------------------------
 // Common productions
 
@@ -450,11 +354,11 @@ func (p *parser) parseQualifiedIdent() ast.Expr {
 		defer un(trace(p, "QualifiedIdent"))
 	}
 
-	var x ast.Expr = p.findIdent()
+	var x ast.Expr = p.parseIdent()
 	if p.tok == token.PERIOD {
 		// first identifier is a package identifier
 		p.next()
-		sel := p.findIdentInScope(nil)
+		sel := p.parseIdent()
 		x = &ast.SelectorExpr{x, sel}
 	}
 	return x
@@ -497,7 +401,7 @@ func (p *parser) makeIdentList(list *vector.Vector) []*ast.Ident {
 		if !isIdent {
 			pos := x.(ast.Expr).Pos()
 			p.errorExpected(pos, "identifier")
-			ident = &ast.Ident{pos, ast.NewObj(ast.Err, pos, "_")}
+			ident = &ast.Ident{pos, "_", nil}
 		}
 		idents[i] = ident
 	}
@@ -565,9 +469,6 @@ func (p *parser) parseStructType() *ast.StructType {
 		fields[i] = x.(*ast.Field)
 	}
 
-	// TODO(gri) The struct scope shouldn't get lost.
-	p.declFieldList(ast.NewScope(nil), fields)
-
 	return &ast.StructType{pos, &ast.FieldList{lbrace, fields, rbrace}, false}
 }
 
@@ -655,7 +556,7 @@ func (p *parser) parseParameterList(ellipsisOk bool) []*ast.Field {
 		}
 
 		for p.tok != token.RPAREN && p.tok != token.EOF {
-			idents := p.parseIdentList(ast.Var)
+			idents := p.parseIdentList()
 			typ := p.parseVarType(ellipsisOk)
 			list.Push(&ast.Field{nil, idents, typ, nil, nil})
 			if p.tok != token.COMMA {
@@ -682,7 +583,7 @@ func (p *parser) parseParameterList(ellipsisOk bool) []*ast.Field {
 }
 
 
-func (p *parser) parseParameters(scope *ast.Scope, ellipsisOk bool) *ast.FieldList {
+func (p *parser) parseParameters(ellipsisOk bool) *ast.FieldList {
 	if p.trace {
 		defer un(trace(p, "Parameters"))
 	}
@@ -691,7 +592,6 @@ func (p *parser) parseParameters(scope *ast.Scope, ellipsisOk bool) *ast.FieldLi
 	lparen := p.expect(token.LPAREN)
 	if p.tok != token.RPAREN {
 		params = p.parseParameterList(ellipsisOk)
-		p.declFieldList(scope, params)
 	}
 	rparen := p.expect(token.RPAREN)
 
@@ -699,13 +599,13 @@ func (p *parser) parseParameters(scope *ast.Scope, ellipsisOk bool) *ast.FieldLi
 }
 
 
-func (p *parser) parseResult(scope *ast.Scope) *ast.FieldList {
+func (p *parser) parseResult() *ast.FieldList {
 	if p.trace {
 		defer un(trace(p, "Result"))
 	}
 
 	if p.tok == token.LPAREN {
-		return p.parseParameters(scope, false)
+		return p.parseParameters(false)
 	}
 
 	typ := p.tryType()
@@ -719,28 +619,27 @@ func (p *parser) parseResult(scope *ast.Scope) *ast.FieldList {
 }
 
 
-func (p *parser) parseSignature(scope *ast.Scope) (params, results *ast.FieldList) {
+func (p *parser) parseSignature() (params, results *ast.FieldList) {
 	if p.trace {
 		defer un(trace(p, "Signature"))
 	}
 
-	params = p.parseParameters(scope, true)
+	params = p.parseParameters(true)
-	results = p.parseResult(scope)
+	results = p.parseResult()
 
 	return
 }
 
 
-func (p *parser) parseFuncType() (*ast.Scope, *ast.FuncType) {
+func (p *parser) parseFuncType() *ast.FuncType {
 	if p.trace {
 		defer un(trace(p, "FuncType"))
 	}
 
 	pos := p.expect(token.FUNC)
-	scope := ast.NewScope(p.funcScope)
+	params, results := p.parseSignature()
-	params, results := p.parseSignature(scope)
 
-	return scope, &ast.FuncType{pos, params, results}
+	return &ast.FuncType{pos, params, results}
 }
 
 
@@ -756,7 +655,7 @@ func (p *parser) parseMethodSpec() *ast.Field {
 	if ident, isIdent := x.(*ast.Ident); isIdent && p.tok == token.LPAREN {
 		// method
 		idents = []*ast.Ident{ident}
-		params, results := p.parseSignature(ast.NewScope(p.funcScope))
+		params, results := p.parseSignature()
 		typ = &ast.FuncType{noPos, params, results}
 	} else {
 		// embedded interface
@@ -787,9 +686,6 @@ func (p *parser) parseInterfaceType() *ast.InterfaceType {
 		methods[i] = x.(*ast.Field)
 	}
 
-	// TODO(gri) The interface scope shouldn't get lost.
-	p.declFieldList(ast.NewScope(nil), methods)
-
 	return &ast.InterfaceType{pos, &ast.FieldList{lbrace, methods, rbrace}, false}
 }
 
@@ -844,8 +740,7 @@ func (p *parser) tryRawType(ellipsisOk bool) ast.Expr {
 	case token.MUL:
 		return p.parsePointerType()
 	case token.FUNC:
-		_, typ := p.parseFuncType()
+		return p.parseFuncType()
-		return typ
 	case token.INTERFACE:
 		return p.parseInterfaceType()
 	case token.MAP:
@@ -894,20 +789,15 @@ func (p *parser) parseStmtList() []ast.Stmt {
 }
 
 
-func (p *parser) parseBody(scope *ast.Scope) *ast.BlockStmt {
+func (p *parser) parseBody() *ast.BlockStmt {
 	if p.trace {
 		defer un(trace(p, "Body"))
 	}
 
-	savedScope := p.funcScope
-	p.funcScope = scope
-
 	lbrace := p.expect(token.LBRACE)
 	list := p.parseStmtList()
 	rbrace := p.expect(token.RBRACE)
 
-	p.funcScope = savedScope
-
 	return &ast.BlockStmt{lbrace, list, rbrace}
 }
 
@@ -917,9 +807,6 @@ func (p *parser) parseBlockStmt() *ast.BlockStmt {
 		defer un(trace(p, "BlockStmt"))
 	}
 
-	p.openScope()
-	defer p.closeScope()
-
 	lbrace := p.expect(token.LBRACE)
 	list := p.parseStmtList()
 	rbrace := p.expect(token.RBRACE)
@@ -936,14 +823,14 @@ func (p *parser) parseFuncTypeOrLit() ast.Expr {
 		defer un(trace(p, "FuncTypeOrLit"))
 	}
 
-	scope, typ := p.parseFuncType()
+	typ := p.parseFuncType()
 	if p.tok != token.LBRACE {
 		// function type only
 		return typ
 	}
 
 	p.exprLev++
-	body := p.parseBody(scope)
+	body := p.parseBody()
 	p.exprLev--
 
 	return &ast.FuncLit{typ, body}
@@ -960,7 +847,7 @@ func (p *parser) parseOperand() ast.Expr {
 
 	switch p.tok {
 	case token.IDENT:
-		return p.findIdent()
+		return p.parseIdent()
 
 	case token.INT, token.FLOAT, token.IMAG, token.CHAR, token.STRING:
 		x := &ast.BasicLit{p.pos, p.tok, p.lit}
@@ -1000,7 +887,7 @@ func (p *parser) parseSelectorOrTypeAssertion(x ast.Expr) ast.Expr {
 	p.expect(token.PERIOD)
 	if p.tok == token.IDENT {
 		// selector
-		sel := p.findIdentInScope(nil)
+		sel := p.parseIdent()
 		return &ast.SelectorExpr{x, sel}
 	}
 
@@ -1445,7 +1332,7 @@ func (p *parser) parseBranchStmt(tok token.Token) *ast.BranchStmt {
 	s := &ast.BranchStmt{p.pos, tok, nil}
 	p.expect(tok)
 	if tok != token.FALLTHROUGH && p.tok == token.IDENT {
-		s.Label = p.findIdentInScope(nil)
+		s.Label = p.parseIdent()
 	}
 	p.expectSemi()
 
@@ -1501,10 +1388,6 @@ func (p *parser) parseIfStmt() *ast.IfStmt {
 		defer un(trace(p, "IfStmt"))
 	}
 
-	// IfStmt block
-	p.openScope()
-	defer p.closeScope()
-
 	pos := p.expect(token.IF)
 	s1, s2, _ := p.parseControlClause(false)
 	body := p.parseBlockStmt()
@@ -1525,10 +1408,6 @@ func (p *parser) parseCaseClause() *ast.CaseClause {
 		defer un(trace(p, "CaseClause"))
 	}
 
-	// CaseClause block
-	p.openScope()
-	defer p.closeScope()
-
 	// SwitchCase
 	pos := p.pos
 	var x []ast.Expr
@@ -1567,10 +1446,6 @@ func (p *parser) parseTypeCaseClause() *ast.TypeCaseClause {
 		defer un(trace(p, "TypeCaseClause"))
 	}
 
-	// TypeCaseClause block
-	p.openScope()
-	defer p.closeScope()
-
 	// TypeSwitchCase
 	pos := p.pos
 	var types []ast.Expr
@@ -1607,10 +1482,6 @@ func (p *parser) parseSwitchStmt() ast.Stmt {
 		defer un(trace(p, "SwitchStmt"))
 	}
 
-	// SwitchStmt block
-	p.openScope()
-	defer p.closeScope()
-
 	pos := p.expect(token.SWITCH)
 	s1, s2, _ := p.parseControlClause(false)
 
@@ -1645,10 +1516,6 @@ func (p *parser) parseCommClause() *ast.CommClause {
 		defer un(trace(p, "CommClause"))
 	}
 
-	// CommClause block
-	p.openScope()
-	defer p.closeScope()
-
 	// CommCase
 	pos := p.pos
 	var tok token.Token
@@ -1709,10 +1576,6 @@ func (p *parser) parseForStmt() ast.Stmt {
 		defer un(trace(p, "ForStmt"))
 	}
 
-	// ForStmt block
-	p.openScope()
-	defer p.closeScope()
-
 	pos := p.expect(token.FOR)
 	s1, s2, s3 := p.parseControlClause(true)
 	body := p.parseBlockStmt()
@@ -1825,14 +1688,10 @@ func parseImportSpec(p *parser, doc *ast.CommentGroup) ast.Spec {
 
 	var ident *ast.Ident
 	if p.tok == token.PERIOD {
-		ident = &ast.Ident{p.pos, ast.NewObj(ast.Pkg, p.pos, ".")}
+		ident = &ast.Ident{p.pos, ".", nil}
 		p.next()
 	} else if p.tok == token.IDENT {
-		ident = p.parseIdent(ast.Pkg)
+		ident = p.parseIdent()
-		// TODO(gri) Make sure the ident is not already declared in the
-		//           package scope. Also, cannot add the same name to
-		//           the package scope later.
-		p.declIdent(p.fileScope, ident)
 	}
 
 	var path *ast.BasicLit
@@ -1853,23 +1712,13 @@ func parseConstSpec(p *parser, doc *ast.CommentGroup) ast.Spec {
 		defer un(trace(p, "ConstSpec"))
 	}
 
-	idents := p.parseIdentList(ast.Con)
+	idents := p.parseIdentList()
-	if p.funcScope == nil {
-		// the scope of a constant outside any function
-		// is the package scope
-		p.declIdentList(p.pkgScope, idents)
-	}
 	typ := p.tryType()
 	var values []ast.Expr
 	if typ != nil || p.tok == token.ASSIGN {
 		p.expect(token.ASSIGN)
 		values = p.parseExprList()
 	}
-	if p.funcScope != nil {
-		// the scope of a constant inside a function
-		// begins after the the ConstSpec
-		p.declIdentList(p.funcScope, idents)
-	}
 	p.expectSemi()
 
 	return &ast.ValueSpec{doc, idents, typ, values, p.lineComment}
@@ -1881,15 +1730,7 @@ func parseTypeSpec(p *parser, doc *ast.CommentGroup) ast.Spec {
 		defer un(trace(p, "TypeSpec"))
 	}
 
-	ident := p.parseIdent(ast.Typ)
+	ident := p.parseIdent()
-	// the scope of a type outside any function is
-	// the package scope; the scope of a type inside
-	// a function starts at the type identifier
-	scope := p.funcScope
-	if scope == nil {
-		scope = p.pkgScope
-	}
-	p.declIdent(scope, ident)
 	typ := p.parseType()
 	p.expectSemi()
 
@@ -1902,23 +1743,13 @@ func parseVarSpec(p *parser, doc *ast.CommentGroup) ast.Spec {
 		defer un(trace(p, "VarSpec"))
 	}
 
-	idents := p.parseIdentList(ast.Var)
+	idents := p.parseIdentList()
-	if p.funcScope == nil {
-		// the scope of a variable outside any function
-		// is the pkgScope
-		p.declIdentList(p.pkgScope, idents)
-	}
 	typ := p.tryType()
 	var values []ast.Expr
 	if typ == nil || p.tok == token.ASSIGN {
 		p.expect(token.ASSIGN)
 		values = p.parseExprList()
 	}
-	if p.funcScope != nil {
-		// the scope of a variable inside a function
-		// begins after the the VarSpec
-		p.declIdentList(p.funcScope, idents)
-	}
 	p.expectSemi()
 
 	return &ast.ValueSpec{doc, idents, typ, values, p.lineComment}
@@ -1956,13 +1787,13 @@ func (p *parser) parseGenDecl(keyword token.Token, f parseSpecFunction) *ast.Gen
 }
 
 
-func (p *parser) parseReceiver(scope *ast.Scope) *ast.FieldList {
+func (p *parser) parseReceiver() *ast.FieldList {
 	if p.trace {
 		defer un(trace(p, "Receiver"))
 	}
 
 	pos := p.pos
-	par := p.parseParameters(scope, false)
+	par := p.parseParameters(false)
 
 	// must have exactly one receiver
 	if par.NumFields() != 1 {
@@ -1990,20 +1821,18 @@ func (p *parser) parseFuncDecl() *ast.FuncDecl {
 
 	doc := p.leadComment
 	pos := p.expect(token.FUNC)
-	scope := ast.NewScope(p.funcScope)
 
 	var recv *ast.FieldList
 	if p.tok == token.LPAREN {
-		recv = p.parseReceiver(scope)
+		recv = p.parseReceiver()
 	}
 
-	ident := p.parseIdent(ast.Fun)
+	ident := p.parseIdent()
-	p.declIdent(p.pkgScope, ident) // there are no local function declarations
+	params, results := p.parseSignature()
-	params, results := p.parseSignature(scope)
 
 	var body *ast.BlockStmt
 	if p.tok == token.LBRACE {
-		body = p.parseBody(scope)
+		body = p.parseBody()
 	}
 	p.expectSemi()
 
@@ -2073,10 +1902,9 @@ func (p *parser) parseFile() *ast.File {
 	// package clause
 	doc := p.leadComment
 	pos := p.expect(token.PACKAGE)
-	ident := p.parseIdent(ast.Pkg) // package name is in no scope
+	ident := p.parseIdent()
 	p.expectSemi()
 
-	p.fileScope = ast.NewScope(p.pkgScope)
 	var decls []ast.Decl
 
 	// Don't bother parsing the rest if we had errors already.

src/pkg/go/parser/parser_test.go

@@ -5,7 +5,6 @@
 package parser
 
 import (
-	"go/ast"
 	"os"
 	"testing"
 )
@@ -21,7 +20,7 @@ var illegalInputs = []interface{}{
 
 func TestParseIllegalInputs(t *testing.T) {
 	for _, src := range illegalInputs {
-		_, err := ParseFile("", src, nil, 0)
+		_, err := ParseFile("", src, 0)
 		if err == nil {
 			t.Errorf("ParseFile(%v) should have failed", src)
 		}
@@ -46,7 +45,7 @@ var validPrograms = []interface{}{
 
 func TestParseValidPrograms(t *testing.T) {
 	for _, src := range validPrograms {
-		_, err := ParseFile("", src, ast.NewScope(nil), 0)
+		_, err := ParseFile("", src, 0)
 		if err != nil {
 			t.Errorf("ParseFile(%q): %v", src, err)
 		}
@@ -62,7 +61,7 @@ var validFiles = []string{
 
 func TestParse3(t *testing.T) {
 	for _, filename := range validFiles {
-		_, err := ParseFile(filename, nil, ast.NewScope(nil), 0)
+		_, err := ParseFile(filename, nil, 0)
 		if err != nil {
 			t.Errorf("ParseFile(%s): %v", filename, err)
 		}

src/pkg/go/printer/nodes.go

@@ -335,7 +335,7 @@ func identListSize(list []*ast.Ident, maxSize int) (size int) {
 		if i > 0 {
 			size += 2 // ", "
 		}
-		size += len(x.Name())
+		size += len(x.Name)
 		if size >= maxSize {
 			break
 		}

src/pkg/go/printer/printer.go

@@ -780,7 +780,7 @@ func (p *printer) print(args ...interface{}) {
 			if p.Styler != nil {
 				data, tag = p.Styler.Ident(x)
 			} else {
-				data = []byte(x.Name())
+				data = []byte(x.Name)
 			}
 			tok = token.IDENT
 		case *ast.BasicLit:

src/pkg/go/printer/printer_test.go

@@ -43,7 +43,7 @@ const (
 
 func check(t *testing.T, source, golden string, mode checkMode) {
 	// parse source
-	prog, err := parser.ParseFile(source, nil, nil, parser.ParseComments)
+	prog, err := parser.ParseFile(source, nil, parser.ParseComments)
 	if err != nil {
 		t.Error(err)
 		return