daily snapshot:

- correctly associate comments with declarations
  (available through AST)
- very raw printing of interface
- much more functionality, now needs some formatting, sorting, etc.

R=r
OCL=26213
CL=26213

usr/gri/pretty/ast.go

@@ -28,6 +28,21 @@ func assert(pred bool) {
 }
 
 
+// ----------------------------------------------------------------------------
+// Comments
+
+type Comment struct {
+	Loc scanner.Location;
+	EndLine int;  // the line where the comment ends
+	Text []byte;
+}
+
+
+// A CommentGroup is a sequence of consequtive comments
+// with no other tokens and no empty lines inbetween.
+type CommentGroup []*Comment
+
+
 // ----------------------------------------------------------------------------
 // Expressions
 
@@ -132,6 +147,7 @@ type (
 		Idents []*Ident;
 		Typ Expr;
 		Tag Expr;  // nil = no tag
+		Comment CommentGroup;
 	};
 
 	StructType struct {
@@ -445,12 +461,14 @@ type (
 		Idents []*Ident;
 		Typ Expr;
 		Vals Expr;
+		Comment CommentGroup;
 	};
 	
 	TypeDecl struct {
 		Loc scanner.Location;  // if > 0: position of "type"
 		Ident *Ident;
 		Typ Expr;
+		Comment CommentGroup;
 	};
 	
 	VarDecl struct {
@@ -458,6 +476,7 @@ type (
 		Idents []*Ident;
 		Typ Expr;
 		Vals Expr;
+		Comment CommentGroup;
 	};
 
 	FuncDecl struct {
@@ -466,6 +485,7 @@ type (
 		Ident *Ident;
 		Sig *Signature;
 		Body *Block;
+		Comment CommentGroup;
 	};
 	
 	DeclList struct {
@@ -500,17 +520,13 @@ func (d *DeclList) Visit(v DeclVisitor) { v.DoDeclList(d); }
 // ----------------------------------------------------------------------------
 // Program
 
-type Comment struct {
-	Loc scanner.Location;
-	Text []byte;
-}
-
-
+// TODO rename to Package
 type Program struct {
 	Loc scanner.Location;  // tok is token.PACKAGE
 	Ident *Ident;
 	Decls []Decl;
-	Comments []*Comment;
+	Comment CommentGroup;
+	Comments []CommentGroup;
 }
 
 

usr/gri/pretty/compilation.go

@@ -112,7 +112,7 @@ func Compile(src_file string, flags *Flags) (*AST.Program, int) {
 	var parser Parser.Parser;
 	parser.Init(&scanner, &err, flags.Verbose);
 
-	prog := parser.ParseProgram();
+	prog := parser.Parse(Parser.ParseEntirePackage);
 
 	if err.nerrors == 0 {
 		TypeChecker.CheckProgram(&err, prog);

usr/gri/pretty/gds.go

@@ -108,7 +108,7 @@ func serveFile(c *http.Conn, filename string) {
 	}
 
 	c.SetHeader("content-type", "text/html; charset=utf-8");
-	Printer.Print(c, true, prog);
+	Printer.Print(c, prog, true);
 }
 
 

usr/gri/pretty/parser.go

@@ -33,7 +33,8 @@ type Parser struct {
 	trace bool;
 	indent uint;
 
-	comments *vector.Vector;
+	comments vector.Vector;
+	last_comment ast.CommentGroup;
 
 	// The next token
 	loc scanner.Location;  // token location
@@ -42,8 +43,6 @@ type Parser struct {
 
 	// Non-syntactic parser control
 	opt_semi bool;  // true if semicolon separator is optional in statement list
-
-	// Nesting levels
 	expr_lev int;  // < 0: in control clause, >= 0: in expression
 };
 
@@ -113,9 +112,63 @@ func (P *Parser) next0() {
 }
 
 
+func (P *Parser) getComment() *ast.Comment {
+	defer P.next0();
+
+	// for /*-style comments, the comment may end on a different line
+	endline := P.loc.Line;
+	if P.val[1] == '*' {
+		for i, b := range P.val {
+			if b == '\n' {
+				endline++;
+			}
+		}
+	}
+	
+	return &ast.Comment{P.loc, endline, P.val};
+}
+
+
+func (P *Parser) getCommentGroup() ast.CommentGroup {
+	list := vector.New(0);
+	
+	// group adjacent comments
+	// (an empty line terminates a group)
+	endline := P.loc.Line;
+	for P.tok == token.COMMENT && endline+1 >= P.loc.Line {
+		c := P.getComment();
+		list.Push(c);
+		endline = c.EndLine;
+	}
+
+	// convert list
+	group := make(ast.CommentGroup, list.Len());
+	for i := 0; i < list.Len(); i++ {
+		group[i] = list.At(i).(*ast.Comment);
+	}
+	
+	return group;
+}
+
+
+func (P *Parser) getLastComment() ast.CommentGroup {
+	c := P.last_comment;
+	if c != nil && c[len(c) - 1].EndLine + 1 < P.loc.Line {
+		// empty line between last comment and current token,
+		// at least one line of space between last comment
+		// and current token; ignore this comment
+		return nil;
+	}
+	return c;
+}
+
+
 func (P *Parser) next() {
-	for P.next0(); P.tok == token.COMMENT; P.next0() {
-		P.comments.Push(&ast.Comment{P.loc, P.val});
+	P.next0();
+	P.last_comment = nil;
+	for P.tok == token.COMMENT {
+		P.last_comment = P.getCommentGroup();
+		P.comments.Push(P.last_comment);
 	}
 }
 
@@ -123,14 +176,9 @@ func (P *Parser) next() {
 func (P *Parser) Init(scanner *scanner.Scanner, err scanner.ErrorHandler, trace bool) {
 	P.scanner = scanner;
 	P.err = err;
-
 	P.trace = trace;
-	P.indent = 0;
-
-	P.comments = vector.New(0);
-
+	P.comments.Init(0);
 	P.next();
-	P.expr_lev = 0;
 }
 
 
@@ -382,20 +430,20 @@ func (P *Parser) parseParameterList(ellipsis_ok bool) []*ast.Field {
 			idents[i] = list.At(i).(*ast.Ident);
 		}
 		list.Init(0);
-		list.Push(&ast.Field{idents, typ, nil});
+		list.Push(&ast.Field{idents, typ, nil, nil});
 
 		for P.tok == token.COMMA {
 			P.next();
 			idents := P.parseIdentList2(nil);
 			typ := P.parseParameterType();
-			list.Push(&ast.Field{idents, typ, nil});
+			list.Push(&ast.Field{idents, typ, nil, nil});
 		}
 
 	} else {
 		// Type { "," Type }
 		// convert list of types into list of *Param
 		for i := 0; i < list.Len(); i++ {
-			list.Set(i, &ast.Field{nil, list.At(i).(ast.Expr), nil});
+			list.Set(i, &ast.Field{nil, list.At(i).(ast.Expr), nil, nil});
 		}
 	}
 
@@ -438,7 +486,7 @@ func (P *Parser) parseResult() []*ast.Field {
 		typ := P.tryType();
 		if typ != nil {
 			result = make([]*ast.Field, 1);
-			result[0] = &ast.Field{nil, typ, nil};
+			result[0] = &ast.Field{nil, typ, nil, nil};
 		}
 	}
 
@@ -495,7 +543,7 @@ func (P *Parser) parseMethodSpec() *ast.Field {
 		typ = x;
 	}
 
-	return &ast.Field{idents, typ, nil};
+	return &ast.Field{idents, typ, nil, nil};
 }
 
 
@@ -558,6 +606,8 @@ func (P *Parser) parseFieldDecl() *ast.Field {
 		defer un(trace(P, "FieldDecl"));
 	}
 
+	comment := P.getLastComment();
+
 	// a list of identifiers looks like a list of type names
 	list := vector.New(0);
 	for {
@@ -601,7 +651,7 @@ func (P *Parser) parseFieldDecl() *ast.Field {
 		}
 	}
 
-	return &ast.Field{idents, typ, tag};
+	return &ast.Field{idents, typ, tag, comment};
 }
 
 
@@ -1377,24 +1427,25 @@ func (P *Parser) parseImportSpec(loc scanner.Location) *ast.ImportDecl {
 }
 
 
-func (P *Parser) parseConstSpec(loc scanner.Location) *ast.ConstDecl {
+func (P *Parser) parseConstSpec(loc scanner.Location, comment ast.CommentGroup) *ast.ConstDecl {
 	if P.trace {
 		defer un(trace(P, "ConstSpec"));
 	}
 
 	idents := P.parseIdentList2(nil);
 	typ := P.tryType();
+
 	var vals ast.Expr;
 	if P.tok == token.ASSIGN {
 		P.next();
 		vals = P.parseExpressionList();
 	}
 
-	return &ast.ConstDecl{loc, idents, typ, vals};
+	return &ast.ConstDecl{loc, idents, typ, vals, comment};
 }
 
 
-func (P *Parser) parseTypeSpec(loc scanner.Location) *ast.TypeDecl {
+func (P *Parser) parseTypeSpec(loc scanner.Location, comment ast.CommentGroup) *ast.TypeDecl {
 	if P.trace {
 		defer un(trace(P, "TypeSpec"));
 	}
@@ -1402,11 +1453,11 @@ func (P *Parser) parseTypeSpec(loc scanner.Location) *ast.TypeDecl {
 	ident := P.parseIdent();
 	typ := P.parseType();
 
-	return &ast.TypeDecl{loc, ident, typ};
+	return &ast.TypeDecl{loc, ident, typ, comment};
 }
 
 
-func (P *Parser) parseVarSpec(loc scanner.Location) *ast.VarDecl {
+func (P *Parser) parseVarSpec(loc scanner.Location, comment ast.CommentGroup) *ast.VarDecl {
 	if P.trace {
 		defer un(trace(P, "VarSpec"));
 	}
@@ -1425,16 +1476,16 @@ func (P *Parser) parseVarSpec(loc scanner.Location) *ast.VarDecl {
 		}
 	}
 
-	return &ast.VarDecl{loc, idents, typ, vals};
+	return &ast.VarDecl{loc, idents, typ, vals, comment};
 }
 
 
-func (P *Parser) parseSpec(loc scanner.Location, keyword int) ast.Decl {
+func (P *Parser) parseSpec(loc scanner.Location, comment ast.CommentGroup, keyword int) ast.Decl {
 	switch keyword {
 	case token.IMPORT: return P.parseImportSpec(loc);
-	case token.CONST: return P.parseConstSpec(loc);
-	case token.TYPE: return P.parseTypeSpec(loc);
-	case token.VAR: return P.parseVarSpec(loc);
+	case token.CONST: return P.parseConstSpec(loc, comment);
+	case token.TYPE: return P.parseTypeSpec(loc, comment);
+	case token.VAR: return P.parseVarSpec(loc, comment);
 	}
 
 	unreachable();
@@ -1447,13 +1498,14 @@ func (P *Parser) parseDecl(keyword int) ast.Decl {
 		defer un(trace(P, "Decl"));
 	}
 
+	comment := P.getLastComment();
 	loc := P.loc;
 	P.expect(keyword);
 	if P.tok == token.LPAREN {
 		P.next();
 		list := vector.New(0);
 		for P.tok != token.RPAREN && P.tok != token.EOF {
-			list.Push(P.parseSpec(noloc, keyword));
+			list.Push(P.parseSpec(noloc, nil, keyword));
 			if P.tok == token.SEMICOLON {
 				P.next();
 			} else {
@@ -1473,7 +1525,7 @@ func (P *Parser) parseDecl(keyword int) ast.Decl {
 		return &ast.DeclList{loc, keyword, decls, end};
 	}
 
-	return P.parseSpec(loc, keyword);
+	return P.parseSpec(loc, comment, keyword);
 }
 
 
@@ -1491,6 +1543,7 @@ func (P *Parser) parseFunctionDecl() *ast.FuncDecl {
 		defer un(trace(P, "FunctionDecl"));
 	}
 
+	comment := P.getLastComment();
 	loc := P.loc;
 	P.expect(token.FUNC);
 
@@ -1513,7 +1566,7 @@ func (P *Parser) parseFunctionDecl() *ast.FuncDecl {
 		body = P.parseBlock(token.LBRACE);
 	}
 
-	return &ast.FuncDecl{loc, recv, ident, sig, body};
+	return &ast.FuncDecl{loc, recv, ident, sig, body, comment};
 }
 
 
@@ -1539,98 +1592,68 @@ func (P *Parser) parseDeclaration() ast.Decl {
 // ----------------------------------------------------------------------------
 // Program
 
-// The top level parsing routines:
-//
-// ParsePackageClause
-// - parses the package clause only and returns the package name
-//
-// ParseImportDecls
-// - parses all import declarations and returns a list of them
-// - the package clause must have been parsed before
-// - useful to determine package dependencies
-//
-// ParseProgram
-// - parses the entire program and returns the complete AST
-
-
-func (P *Parser) ParsePackageClause() *ast.Ident {
-	if P.trace {
-		defer un(trace(P, "PackageClause"));
-	}
-
-	P.expect(token.PACKAGE);
-	return P.parseIdent();
-}
-
-
-func (P *Parser) parseImportDecls() *vector.Vector {
-	if P.trace {
-		defer un(trace(P, "ImportDecls"));
-	}
-
-	list := vector.New(0);
-	for P.tok == token.IMPORT {
-		list.Push(P.parseDecl(token.IMPORT));
-		if P.tok == token.SEMICOLON {
-			P.next();
-		}
-	}
-
-	return list;
-}
-
-
-func (P *Parser) ParseImportDecls() []ast.Decl {
-	list := P.parseImportDecls();
-
-	// convert list
-	imports := make([]ast.Decl, list.Len());
-	for i := 0; i < list.Len(); i++ {
-		imports[i] = list.At(i).(ast.Decl);
-	}
-
-	return imports;
-}
-
-
-// Returns the list of comments accumulated during parsing, if any.
-// (The scanner must return token.COMMENT tokens for comments to be
-// collected in the first place.)
-
-func (P *Parser) Comments() []*ast.Comment {
+func (P *Parser) getComments() []ast.CommentGroup {
 	// convert comments vector
-	list := make([]*ast.Comment, P.comments.Len());
+	list := make([]ast.CommentGroup, P.comments.Len());
 	for i := 0; i < P.comments.Len(); i++ {
-		list[i] = P.comments.At(i).(*ast.Comment);
+		list[i] = P.comments.At(i).(ast.CommentGroup);
 	}
 	return list;
 }
 
 
-func (P *Parser) ParseProgram() *ast.Program {
+// The Parse function is parametrized with one of the following
+// constants. They control how much of the source text is parsed.
+//
+const (
+	ParseEntirePackage = iota;
+	ParseImportDeclsOnly;
+	ParsePackageClauseOnly;
+)
+
+
+// Parse parses the source...
+//      
+// foo bar
+//
+func (P *Parser) Parse(mode int) *ast.Program {
 	if P.trace {
 		defer un(trace(P, "Program"));
 	}
 
-	p := ast.NewProgram(P.loc);
-	p.Ident = P.ParsePackageClause();
+	// package clause
+	comment := P.getLastComment();
+	loc := P.loc;
+	P.expect(token.PACKAGE);
+	name := P.parseIdent();
+	var decls []ast.Decl;
 
-	// package body
-	list := P.parseImportDecls();
-	for P.tok != token.EOF {
-		list.Push(P.parseDeclaration());
-		if P.tok == token.SEMICOLON {
-			P.next();
+	if mode <= ParseImportDeclsOnly {
+		// import decls
+		list := vector.New(0);
+		for P.tok == token.IMPORT {
+			list.Push(P.parseDecl(token.IMPORT));
+			if P.tok == token.SEMICOLON {
+				P.next();
+			}
 		}
-	}
 
-	// convert list
-	p.Decls = make([]ast.Decl, list.Len());
-	for i := 0; i < list.Len(); i++ {
-		p.Decls[i] = list.At(i).(ast.Decl);
-	}
+		if mode <= ParseEntirePackage {
+			// rest of package body
+			for P.tok != token.EOF {
+				list.Push(P.parseDeclaration());
+				if P.tok == token.SEMICOLON {
+					P.next();
+				}
+			}
+		}
 
-	p.Comments = P.Comments();
+		// convert list
+		decls = make([]ast.Decl, list.Len());
+		for i := 0; i < list.Len(); i++ {
+			decls[i] = list.At(i).(ast.Decl);
+		}
+	}
 
-	return p;
+	return &ast.Program{loc, name, decls, comment, P.getComments()};
 }

usr/gri/pretty/pretty.go

@@ -53,7 +53,7 @@ func main() {
 				sys.Exit(1);
 			}
 			if !*silent {
-				Printer.Print(os.Stdout, *html, prog);
+				Printer.Print(os.Stdout, prog, *html);
 			}
 		}
 	}

usr/gri/pretty/printer.go

@@ -24,12 +24,11 @@ import (
 
 var (
 	debug = flag.Bool("debug", false, "print debugging information");
-	def = flag.Bool("def", false, "print 'def' instead of 'const', 'type', 'func' - experimental");
 
 	// layout control
 	tabwidth = flag.Int("tabwidth", 8, "tab width");
 	usetabs = flag.Bool("usetabs", true, "align with tabs instead of blanks");
-	newlines = flag.Bool("newlines", true, "respect newlines in source");
+	newlines = flag.Bool("newlines", false, "respect newlines in source");
 	maxnewlines = flag.Int("maxnewlines", 3, "max. number of consecutive newlines");
 
 	// formatting control
@@ -63,6 +62,23 @@ func assert(pred bool) {
 }
 
 
+// TODO this should be an AST method
+func isExported(name *ast.Ident) bool {
+	ch, len := utf8.DecodeRuneInString(name.Str, 0);
+	return unicode.IsUpper(ch);
+}
+
+
+func hasExportedNames(names []*ast.Ident) bool {
+	for i, name := range names {
+		if isExported(name) {
+			return true;
+		}
+	}
+	return false;
+}
+
+
 // ----------------------------------------------------------------------------
 // Printer
 
@@ -91,14 +107,15 @@ type Printer struct {
 	
 	// formatting control
 	html bool;
+	full bool;  // if false, print interface only; print all otherwise
 
 	// comments
-	comments []*ast.Comment;  // the list of all comments
-	cindex int;  // the current comments index
-	cpos int;  // the position of the next comment
+	comments []ast.CommentGroup;  // the list of all comments groups
+	cindex int;  // the current comment group index
+	cloc scanner.Location;  // the position of the next comment group
 
 	// current state
-	lastpos int;  // pos after last string
+	lastloc scanner.Location;  // location after last string
 	level int;  // scope level
 	indentation int;  // indentation level (may be different from scope level)
 
@@ -116,22 +133,22 @@ type Printer struct {
 }
 
 
-func (P *Printer) HasComment(pos int) bool {
-	return *comments && P.cpos < pos;
+func (P *Printer) hasComment(loc scanner.Location) bool {
+	return *comments && P.cloc.Pos < loc.Pos;
 }
 
 
-func (P *Printer) NextComment() {
+func (P *Printer) nextCommentGroup() {
 	P.cindex++;
 	if P.comments != nil && P.cindex < len(P.comments) {
-		P.cpos = P.comments[P.cindex].Loc.Pos;
+		P.cloc = P.comments[P.cindex][0].Loc;
 	} else {
-		P.cpos = 1<<30;  // infinite
+		P.cloc = scanner.Location{1<<30, 1<<30, 1};  // infinite
 	}
 }
 
 
-func (P *Printer) Init(text io.Write, html bool, comments []*ast.Comment) {
+func (P *Printer) Init(text io.Write, comments []ast.CommentGroup, html bool) {
 	// writers
 	P.text = text;
 	
@@ -141,7 +158,7 @@ func (P *Printer) Init(text io.Write, html bool, comments []*ast.Comment) {
 	// comments
 	P.comments = comments;
 	P.cindex = -1;
-	P.NextComment();
+	P.nextCommentGroup();
 
 	// formatting parameters & semantic state initialized correctly by default
 	
@@ -194,14 +211,15 @@ func (P *Printer) Printf(format string, s ...) {
 }
 
 
-func (P *Printer) Newline(n int) {
+func (P *Printer) newline(n int) {
 	if n > 0 {
 		m := int(*maxnewlines);
 		if n > m {
 			n = m;
 		}
-		for ; n > 0; n-- {
+		for n > 0 {
 			P.Printf("\n");
+			n--;
 		}
 		for i := P.indentation; i > 0; i-- {
 			P.Printf("\t");
@@ -214,7 +232,7 @@ func (P *Printer) TaggedString(loc scanner.Location, tag, s, endtag string) {
 	// use estimate for pos if we don't have one
 	pos := loc.Pos;
 	if pos == 0 {
-		pos = P.lastpos;
+		pos = P.lastloc.Pos;
 	}
 
 	// --------------------------------
@@ -252,26 +270,22 @@ func (P *Printer) TaggedString(loc scanner.Location, tag, s, endtag string) {
 	// --------------------------------
 	// interleave comments, if any
 	nlcount := 0;
-	for ; P.HasComment(pos); P.NextComment() {
-		// we have a comment/newline that comes before the string
-		comment := P.comments[P.cindex];
-		ctext := string(comment.Text);  // TODO get rid of string conversion here
-
-		if ctext == "\n" {
-			// found a newline in src - count it
-			nlcount++;
+	if P.full {
+		for ; P.hasComment(loc); P.nextCommentGroup() {
+			// we have a comment group that comes before the string
+			comment := P.comments[P.cindex][0];  // TODO broken
+			ctext := string(comment.Text);  // TODO get rid of string conversion here
 
-		} else {
 			// classify comment (len(ctext) >= 2)
 			//-style comment
-			if nlcount > 0 || P.cpos == 0 {
+			if nlcount > 0 || P.cloc.Pos == 0 {
 				// only white space before comment on this line
 				// or file starts with comment
 				// - indent
-				if !*newlines && P.cpos != 0 {
+				if !*newlines && P.cloc.Pos != 0 {
 					nlcount = 1;
 				}
-				P.Newline(nlcount);
+				P.newline(nlcount);
 				nlcount = 0;
 
 			} else {
@@ -304,23 +318,16 @@ func (P *Printer) TaggedString(loc scanner.Location, tag, s, endtag string) {
 
 			// print comment
 			if *debug {
-				P.Printf("[%d]", P.cpos);
+				P.Printf("[%d]", P.cloc.Pos);
 			}
 			// calling untabify increases the change for idempotent output
 			// since tabs in comments are also interpreted by tabwriter
 			P.Printf("%s", P.htmlEscape(untabify(ctext)));
-
-			if ctext[1] == '/' {
-				//-style comments must end in newline
-				if P.newlines == 0 {  // don't add newlines if not needed
-					P.newlines = 1;
-				}
-			}
 		}
+		// At this point we may have nlcount > 0: In this case we found newlines
+		// that were not followed by a comment. They are recognized (or not) when
+		// printing newlines below.
 	}
-	// At this point we may have nlcount > 0: In this case we found newlines
-	// that were not followed by a comment. They are recognized (or not) when
-	// printing newlines below.
 
 	// --------------------------------
 	// interpret state
@@ -346,7 +353,7 @@ func (P *Printer) TaggedString(loc scanner.Location, tag, s, endtag string) {
 		P.newlines = nlcount;
 	}
 	nlcount = 0;
-	P.Newline(P.newlines);
+	P.newline(P.newlines);
 	P.newlines = 0;
 
 	// --------------------------------
@@ -375,7 +382,9 @@ func (P *Printer) TaggedString(loc scanner.Location, tag, s, endtag string) {
 	// --------------------------------
 	// done
 	P.opt_semi = false;
-	P.lastpos = pos + len(s);  // rough estimate
+	loc.Pos += len(s);  // rough estimate
+	loc.Col += len(s);  // rough estimate
+	P.lastloc = loc;
 }
 
 
@@ -437,15 +446,20 @@ func (P *Printer) HtmlPackageName(loc scanner.Location, name string) {
 
 func (P *Printer) Expr(x ast.Expr)
 
-func (P *Printer) Idents(list []*ast.Ident) {
+func (P *Printer) Idents(list []*ast.Ident, full bool) int {
+	n := 0;
 	for i, x := range list {
-		if i > 0 {
+		if n > 0 {
 			P.Token(noloc, token.COMMA);
 			P.separator = blank;
 			P.state = inside_list;
 		}
-		P.Expr(x);
+		if full || isExported(x) {
+			P.Expr(x);
+			n++;
+		}
 	}
+	return n;
 }
 
 
@@ -456,8 +470,8 @@ func (P *Printer) Parameters(list []*ast.Field) {
 			if i > 0 {
 				P.separator = comma;
 			}
-			if len(par.Idents) > 0 {
-				P.Idents(par.Idents);
+			n := P.Idents(par.Idents, true);
+			if n > 0 {
 				P.separator = blank
 			};
 			P.Expr(par.Typ);
@@ -501,21 +515,25 @@ func (P *Printer) Fields(list []*ast.Field, end scanner.Location, is_interface b
 				P.separator = semicolon;
 				P.newlines = 1;
 			}
-			if len(fld.Idents) > 0 {
-				P.Idents(fld.Idents);
+			n := P.Idents(fld.Idents, P.full);
+			if n > 0 {
+				// at least one identifier
 				P.separator = tab
 			};
-			if is_interface {
-				if ftyp, is_ftyp := fld.Typ.(*ast.FunctionType); is_ftyp {
-					P.Signature(ftyp.Sig);
+			if n > 0 || len(fld.Idents) == 0 {
+				// at least one identifier or anonymous field
+				if is_interface {
+					if ftyp, is_ftyp := fld.Typ.(*ast.FunctionType); is_ftyp {
+						P.Signature(ftyp.Sig);
+					} else {
+						P.Expr(fld.Typ);
+					}
 				} else {
 					P.Expr(fld.Typ);
-				}
-			} else {
-				P.Expr(fld.Typ);
-				if fld.Tag != nil {
-					P.separator = tab;
-					P.Expr(fld.Tag);
+					if fld.Tag != nil {
+						P.separator = tab;
+						P.Expr(fld.Tag);
+					}
 				}
 			}
 		}
@@ -977,7 +995,7 @@ func (P *Printer) DoConstDecl(d *ast.ConstDecl) {
 		P.Token(d.Loc, token.CONST);
 		P.separator = blank;
 	}
-	P.Idents(d.Idents);
+	P.Idents(d.Idents, P.full);
 	if d.Typ != nil {
 		P.separator = blank;  // TODO switch to tab? (indentation problem with structs)
 		P.Expr(d.Typ);
@@ -1009,7 +1027,7 @@ func (P *Printer) DoVarDecl(d *ast.VarDecl) {
 		P.Token(d.Loc, token.VAR);
 		P.separator = blank;
 	}
-	P.Idents(d.Idents);
+	P.Idents(d.Idents, P.full);
 	if d.Typ != nil {
 		P.separator = blank;  // TODO switch to tab? (indentation problem with structs)
 		P.Expr(d.Typ);
@@ -1025,7 +1043,7 @@ func (P *Printer) DoVarDecl(d *ast.VarDecl) {
 }
 
 
-func (P *Printer) funcDecl(d *ast.FuncDecl, with_body bool) {
+func (P *Printer) DoFuncDecl(d *ast.FuncDecl) {
 	P.Token(d.Loc, token.FUNC);
 	P.separator = blank;
 	if recv := d.Recv; recv != nil {
@@ -1041,7 +1059,7 @@ func (P *Printer) funcDecl(d *ast.FuncDecl, with_body bool) {
 	}
 	P.Expr(d.Ident);
 	P.Signature(d.Sig);
-	if with_body && d.Body != nil {
+	if P.full && d.Body != nil {
 		P.separator = blank;
 		P.Block(d.Body, true);
 	}
@@ -1049,17 +1067,8 @@ func (P *Printer) funcDecl(d *ast.FuncDecl, with_body bool) {
 }
 
 
-func (P *Printer) DoFuncDecl(d *ast.FuncDecl) {
-	P.funcDecl(d, true);
-}
-
-
 func (P *Printer) DoDeclList(d *ast.DeclList) {
-	if !*def || d.Tok == token.IMPORT || d.Tok == token.VAR {
-		P.Token(d.Loc, d.Tok);
-	} else {
-		P.String(d.Loc, "def");
-	}
+	P.Token(d.Loc, d.Tok);
 	P.separator = blank;
 
 	// group of parenthesized declarations
@@ -1090,26 +1099,111 @@ func (P *Printer) Decl(d ast.Decl) {
 // ----------------------------------------------------------------------------
 // Package interface
 
-// TODO this should be an AST method
-func isExported(name *ast.Ident) bool {
-	ch, len := utf8.DecodeRuneInString(name.Str, 0);
-	return unicode.IsUpper(ch);
+func stripWhiteSpace(s []byte) []byte {
+	i, j := 0, len(s);
+	for i < len(s) && s[i] <= ' ' {
+		i++;
+	}
+	for j > i && s[j-1] <= ' ' {
+		j--
+	}
+	return s[i : j];
+}
+
+
+func cleanComment(s []byte) []byte {
+	switch s[1] {
+	case '/': s = s[2 : len(s)-1];
+	case '*': s = s[2 : len(s)-2];
+	default : panic("illegal comment");
+	}
+	return stripWhiteSpace(s);
+}
+
+
+func (P *Printer) printComment(comment ast.CommentGroup) {
+	in_paragraph := false;
+	for i, c := range comment {
+		s := cleanComment(c.Text);
+		if len(s) > 0 {
+			if !in_paragraph {
+				P.Printf("<p>\n");
+				in_paragraph = true;
+			}
+			P.Printf("%s\n", P.htmlEscape(untabify(string(s))));
+		} else {
+			if in_paragraph {
+				P.Printf("</p>\n");
+				in_paragraph = false;
+			}
+		}
+	}
+	if in_paragraph {
+		P.Printf("</p>\n");
+	}
 }
 
 
 func (P *Printer) Interface(p *ast.Program) {
+	P.full = false;
 	for i := 0; i < len(p.Decls); i++ {
 		switch d := p.Decls[i].(type) {
+		case *ast.ConstDecl:
+			if hasExportedNames(d.Idents) {
+				P.Printf("<h2>Constants</h2>\n");
+				P.Printf("<p><pre>");
+				P.DoConstDecl(d);
+				P.String(noloc, "");
+				P.Printf("</pre></p>\n");
+				if d.Comment != nil {
+					P.printComment(d.Comment);
+				}
+			}
+
+		case *ast.TypeDecl:
+			if isExported(d.Ident) {
+				P.Printf("<h2>type %s</h2>\n", d.Ident.Str);
+				P.Printf("<p><pre>");
+				P.DoTypeDecl(d);
+				P.String(noloc, "");
+				P.Printf("</pre></p>\n");
+				if d.Comment != nil {
+					P.printComment(d.Comment);
+				}
+			}
+
+		case *ast.VarDecl:
+			if hasExportedNames(d.Idents) {
+				P.Printf("<h2>Variables</h2>\n");
+				P.Printf("<p><pre>");
+				P.DoVarDecl(d);
+				P.String(noloc, "");
+				P.Printf("</pre></p>\n");
+				if d.Comment != nil {
+					P.printComment(d.Comment);
+				}
+			}
+
 		case *ast.FuncDecl:
 			if isExported(d.Ident) {
-				P.Printf("<h2>%s</h2>\n", d.Ident.Str);
-				/*
+				if d.Recv != nil {
+					P.Printf("<h3>func (");
+					P.Expr(d.Recv.Typ);
+					P.Printf(") %s</h3>\n", d.Ident.Str);
+				} else {
+					P.Printf("<h2>func %s</h2>\n", d.Ident.Str);
+				}
 				P.Printf("<p><code>");
-				P.funcDecl(d, false);
+				P.DoFuncDecl(d);
 				P.String(noloc, "");
-				P.Printf("</code></p>");
-				*/
+				P.Printf("</code></p>\n");
+				if d.Comment != nil {
+					P.printComment(d.Comment);
+				}
 			}
+			
+		case *ast.DeclList:
+			
 		}
 	}
 }
@@ -1119,6 +1213,7 @@ func (P *Printer) Interface(p *ast.Program) {
 // Program
 
 func (P *Printer) Program(p *ast.Program) {
+	P.full = true;
 	P.Token(p.Loc, token.PACKAGE);
 	P.separator = blank;
 	P.Expr(p.Ident);
@@ -1140,7 +1235,7 @@ func init() {
 }
 
 
-func Print(writer io.Write, html bool, prog *ast.Program) {
+func Print(writer io.Write, prog *ast.Program, html bool) {
 	// setup
 	var P Printer;
 	padchar := byte(' ');
@@ -1152,13 +1247,14 @@ func Print(writer io.Write, html bool, prog *ast.Program) {
 		flags |= tabwriter.FilterHTML;
 	}
 	text := tabwriter.NewWriter(writer, *tabwidth, 1, padchar, flags);
-	P.Init(text, html, prog.Comments);
+	P.Init(text, nil /* prog.Comments */, html);
 
 	if P.html {
 		err := templ.Apply(text, "<!--", template.Substitution {
-			"PACKAGE-->" : func() { P.Printf("%s", prog.Ident.Str); },
-			"INTERFACE-->" : func() { P.Interface(prog); },
-			"BODY-->" : func() { P.Program(prog); },
+			"PACKAGE_NAME-->" : func() { P.Printf("%s", prog.Ident.Str); },
+			"PACKAGE_COMMENT-->": func() { P.printComment(prog.Comment); },
+			"PACKAGE_INTERFACE-->" : func() { P.Interface(prog); },
+			"PACKAGE_BODY-->" : func() { P.Program(prog); },
 		});
 		if err != nil {
 			panic("print error - exiting");

usr/gri/pretty/template.html

 
-<h1>package <!--PACKAGE--></h1>
+<font color=red>THIS SECTION IS CURRENTLY UNDER CONSTRUCTION</font>
 
-<!--INTERFACE-->
+<h1>package <!--PACKAGE_NAME--></h1>
+<!--PACKAGE_COMMENT-->
+<!--PACKAGE_INTERFACE-->
 
 <hr />
-
-<h1>package <!--PACKAGE--></h1>
+<h1>Implementation</h1>
+<font color=grey>Comments are currently not shown in the source.</font>
 
 <pre>
-<!--BODY-->
+<!--PACKAGE_BODY-->
 </pre>
 
 </div>  <!-- content -->