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mirror of https://github.com/golang/go synced 2024-11-25 07:57:56 -07:00
go/usr/gri/pretty/astprinter.go
Robert Griesemer 2a9f1ee215 Daily snapshot.
- godoc now supports the following url prefixes:
  /doc/ for package documentation
  /file/ for files (directories, html, and .go files)
  /spec for the spec
  /mem for the memory model
- formatting of comments has been fixed
- tons of minor cleanups (still more to do)

Still missing:
- pretty printing of source is not as pretty as it used to be
(still a relict from the massive AST cleanup which has't quite made it's way everywhere)
- documentation entries should be sorted
- comments in code is not printed or not properly printed

TBR=r
DELTA=416  (182 added, 100 deleted, 134 changed)
OCL=27078
CL=27078
2009-04-03 16:19:22 -07:00

1294 lines
26 KiB
Go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package astPrinter
import (
"ast";
"flag";
"fmt";
"io";
"os";
"strings";
"tabwriter";
"token";
"unicode";
"utf8";
"vector";
)
var (
debug = flag.Bool("ast_debug", false, "print debugging information");
// layout control
newlines = flag.Bool("ast_newlines", false, "respect newlines in source");
maxnewlines = flag.Int("ast_maxnewlines", 3, "max. number of consecutive newlines");
// formatting control
comments = flag.Bool("ast_comments", true, "print comments");
optsemicolons = flag.Bool("ast_optsemicolons", false, "print optional semicolons");
)
// When we don't have a position use noPos.
var noPos token.Position;
// ----------------------------------------------------------------------------
// Elementary support
func unimplemented() {
panic("unimplemented");
}
func unreachable() {
panic("unreachable");
}
func assert(pred bool) {
if !pred {
panic("assertion failed");
}
}
// TODO this should be an AST method
func isExported(name *ast.Ident) bool {
ch, len := utf8.DecodeRuneInString(name.Value, 0);
return unicode.IsUpper(ch);
}
func hasExportedNames(names []*ast.Ident) bool {
for i, name := range names {
if isExported(name) {
return true;
}
}
return false;
}
// ----------------------------------------------------------------------------
// TokenPrinter
// TODO This is not yet used - should fix this.
// An implementation of a TokenPrinter may be provided when
// initializing an AST Printer. It is used to print tokens.
//
type TokenPrinter interface {
PrintLit(w io.Write, tok token.Token, value []byte);
PrintIdent(w io.Write, value string);
PrintToken(w io.Write, token token.Token);
PrintComment(w io.Write, value []byte);
}
type defaultPrinter struct {}
func (p defaultPrinter) PrintLit(w io.Write, tok token.Token, value []byte) {
w.Write(value);
}
func (p defaultPrinter) PrintIdent(w io.Write, value string) {
fmt.Fprint(w, value);
}
func (p defaultPrinter) PrintToken(w io.Write, token token.Token) {
fmt.Fprint(w, token.String());
}
func (p defaultPrinter) PrintComment(w io.Write, value []byte) {
w.Write(value);
}
// ----------------------------------------------------------------------------
// ASTPrinter
// Separators - printed in a delayed fashion, depending on context.
const (
none = iota;
blank;
tab;
comma;
semicolon;
)
// Semantic states - control formatting.
const (
normal = iota;
opening_scope; // controls indentation, scope level
closing_scope; // controls indentation, scope level
inside_list; // controls extra line breaks
)
type Printer struct {
// output
text io.Write;
// token printing
tprinter TokenPrinter;
// formatting control
html bool;
full bool; // if false, print interface only; print all otherwise
// comments
comments []*ast.Comment; // the list of unassociated comments
cindex int; // the current comment index
cpos token.Position; // the position of the next comment
// current state
lastpos token.Position; // position after last string
level int; // scope level
indentation int; // indentation level (may be different from scope level)
// formatting parameters
opt_semi bool; // // true if semicolon separator is optional in statement list
separator int; // pending separator
newlines int; // pending newlines
// semantic state
state int; // current semantic state
laststate int; // state for last string
// expression precedence
prec int;
}
func (P *Printer) hasComment(pos token.Position) bool {
return *comments && P.cpos.Offset < pos.Offset;
}
func (P *Printer) nextComments() {
P.cindex++;
if P.comments != nil && P.cindex < len(P.comments) && P.comments[P.cindex] != nil {
P.cpos = P.comments[P.cindex].Pos();
} else {
P.cpos = token.Position{1<<30, 1<<30, 1}; // infinite
}
}
func (P *Printer) Init(text io.Write, tprinter TokenPrinter, comments []*ast.Comment, html bool) {
// writers
P.text = text;
// token printing
if tprinter != nil {
P.tprinter = tprinter;
} else {
P.tprinter = defaultPrinter{};
}
// formatting control
P.html = html;
// comments
P.comments = comments;
P.cindex = -1;
P.nextComments();
// formatting parameters & semantic state initialized correctly by default
// expression precedence
P.prec = token.LowestPrec;
}
// ----------------------------------------------------------------------------
// Printing support
func (P *Printer) htmlEscape(s string) string {
if P.html {
var esc string;
for i := 0; i < len(s); i++ {
switch s[i] {
case '<': esc = "&lt;";
case '&': esc = "&amp;";
default: continue;
}
return s[0 : i] + esc + P.htmlEscape(s[i+1 : len(s)]);
}
}
return s;
}
// Reduce contiguous sequences of '\t' in a string to a single '\t'.
func untabify(s string) string {
for i := 0; i < len(s); i++ {
if s[i] == '\t' {
j := i;
for j < len(s) && s[j] == '\t' {
j++;
}
if j-i > 1 { // more then one tab
return s[0 : i+1] + untabify(s[j : len(s)]);
}
}
}
return s;
}
func (P *Printer) Printf(format string, s ...) {
n, err := fmt.Fprintf(P.text, format, s);
if err != nil {
panic("print error - exiting");
}
}
func (P *Printer) newline(n int) {
if n > 0 {
m := int(*maxnewlines);
if n > m {
n = m;
}
for n > 0 {
P.Printf("\n");
n--;
}
for i := P.indentation; i > 0; i-- {
P.Printf("\t");
}
}
}
func (P *Printer) TaggedString(pos token.Position, tag, s, endtag string) {
// use estimate for pos if we don't have one
offs := pos.Offset;
if pos.Line == 0 {
offs = P.lastpos.Offset;
}
// --------------------------------
// print pending separator, if any
// - keep track of white space printed for better comment formatting
// TODO print white space separators after potential comments and newlines
// (currently, we may get trailing white space before a newline)
trailing_char := 0;
switch P.separator {
case none: // nothing to do
case blank:
P.Printf(" ");
trailing_char = ' ';
case tab:
P.Printf("\t");
trailing_char = '\t';
case comma:
P.Printf(",");
if P.newlines == 0 {
P.Printf(" ");
trailing_char = ' ';
}
case semicolon:
if P.level > 0 { // no semicolons at level 0
P.Printf(";");
if P.newlines == 0 {
P.Printf(" ");
trailing_char = ' ';
}
}
default: panic("UNREACHABLE");
}
P.separator = none;
// --------------------------------
// interleave comments, if any
nlcount := 0;
if P.full {
for ; P.hasComment(pos); P.nextComments() {
// we have a comment group that comes before the string
comment := P.comments[P.cindex];
ctext := string(comment.Text); // TODO get rid of string conversion here
// classify comment (len(ctext) >= 2)
//-style comment
if nlcount > 0 || P.cpos.Offset == 0 {
// only white space before comment on this line
// or file starts with comment
// - indent
if !*newlines && P.cpos.Offset != 0 {
nlcount = 1;
}
P.newline(nlcount);
nlcount = 0;
} else {
// black space before comment on this line
if ctext[1] == '/' {
//-style comment
// - put in next cell unless a scope was just opened
// in which case we print 2 blanks (otherwise the
// entire scope gets indented like the next cell)
if P.laststate == opening_scope {
switch trailing_char {
case ' ': P.Printf(" "); // one space already printed
case '\t': // do nothing
default: P.Printf(" ");
}
} else {
if trailing_char != '\t' {
P.Printf("\t");
}
}
} else {
/*-style comment */
// - print surrounded by blanks
if trailing_char == 0 {
P.Printf(" ");
}
ctext += " ";
}
}
// print comment
if *debug {
P.Printf("[%d]", P.cpos.Offset);
}
// calling untabify increases the change for idempotent output
// since tabs in comments are also interpreted by tabwriter
P.Printf("%s", P.htmlEscape(untabify(ctext)));
}
// 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
// (any pending separator or comment must be printed in previous state)
switch P.state {
case normal:
case opening_scope:
case closing_scope:
P.indentation--;
case inside_list:
default:
panic("UNREACHABLE");
}
// --------------------------------
// print pending newlines
if *newlines && (P.newlines > 0 || P.state == inside_list) && nlcount > P.newlines {
// Respect additional newlines in the source, but only if we
// enabled this feature (newlines.BVal()) and we are expecting
// newlines (P.newlines > 0 || P.state == inside_list).
// Otherwise - because we don't have all token positions - we
// get funny formatting.
P.newlines = nlcount;
}
nlcount = 0;
P.newline(P.newlines);
P.newlines = 0;
// --------------------------------
// print string
if *debug {
P.Printf("[%d]", pos);
}
P.Printf("%s%s%s", tag, P.htmlEscape(s), endtag);
// --------------------------------
// interpret state
switch P.state {
case normal:
case opening_scope:
P.level++;
P.indentation++;
case closing_scope:
P.level--;
case inside_list:
default:
panic("UNREACHABLE");
}
P.laststate = P.state;
P.state = none;
// --------------------------------
// done
P.opt_semi = false;
pos.Offset += len(s); // rough estimate
pos.Column += len(s); // rough estimate
P.lastpos = pos;
}
func (P *Printer) String(pos token.Position, s string) {
P.TaggedString(pos, "", s, "");
}
func (P *Printer) Token(pos token.Position, tok token.Token) {
P.String(pos, tok.String());
//P.TaggedString(pos, "<b>", tok.String(), "</b>");
}
func (P *Printer) Error(pos token.Position, tok token.Token, msg string) {
fmt.Printf("\ninternal printing error: pos = %d, tok = %s, %s\n", pos.Offset, tok.String(), msg);
panic();
}
// An astPrinter implements io.Write.
// TODO this is not yet used.
func (P *Printer) Write(p []byte) (n int, err *os.Error) {
// TODO
// - no string conversion every time
// - return proper results
P.String(noPos, string(p));
return len(p), nil;
}
// ----------------------------------------------------------------------------
// HTML support
func (P *Printer) HtmlIdentifier(x *ast.Ident) {
P.String(x.Pos(), x.Value);
/*
obj := x.Obj;
if P.html && obj.Kind != symbolTable.NONE {
// depending on whether we have a declaration or use, generate different html
// - no need to htmlEscape ident
id := utils.IntToString(obj.Id, 10);
if x.Loc_ == obj.Pos {
// probably the declaration of x
P.TaggedString(x.Loc_, `<a name="id` + id + `">`, obj.Ident, `</a>`);
} else {
// probably not the declaration of x
P.TaggedString(x.Loc_, `<a href="#id` + id + `">`, obj.Ident, `</a>`);
}
} else {
P.String(x.Loc_, obj.Ident);
}
*/
}
func (P *Printer) HtmlPackageName(pos token.Position, name string) {
if P.html {
sname := name[1 : len(name)-1]; // strip quotes TODO do this elsewhere eventually
// TODO CAPITAL HACK BELOW FIX THIS
P.TaggedString(pos, `"<a href="/src/lib/` + sname + `.go">`, sname, `</a>"`);
} else {
P.String(pos, name);
}
}
// ----------------------------------------------------------------------------
// Support
func (P *Printer) Expr(x ast.Expr)
func (P *Printer) Idents(list []*ast.Ident, full bool) int {
n := 0;
for i, x := range list {
if n > 0 {
P.Token(noPos, token.COMMA);
P.separator = blank;
P.state = inside_list;
}
if full || isExported(x) {
P.Expr(x);
n++;
}
}
return n;
}
func (P *Printer) Exprs(list []ast.Expr) {
for i, x := range list {
if i > 0 {
P.Token(noPos, token.COMMA);
P.separator = blank;
P.state = inside_list;
}
P.Expr(x);
}
}
func (P *Printer) Parameters(list []*ast.Field) {
P.Token(noPos, token.LPAREN);
if len(list) > 0 {
for i, par := range list {
if i > 0 {
P.separator = comma;
}
n := P.Idents(par.Names, true);
if n > 0 {
P.separator = blank
};
P.Expr(par.Type);
}
}
P.Token(noPos, token.RPAREN);
}
// Returns the separator (semicolon or none) required if
// the type is terminating a declaration or statement.
func (P *Printer) Signature(params, result []*ast.Field) {
P.Parameters(params);
if result != nil {
P.separator = blank;
if len(result) == 1 && result[0].Names == nil {
// single anonymous result
// => no parentheses needed unless it's a function type
fld := result[0];
if dummy, is_ftyp := fld.Type.(*ast.FuncType); !is_ftyp {
P.Expr(fld.Type);
return;
}
}
P.Parameters(result);
}
}
func (P *Printer) Fields(lbrace token.Position, list []*ast.Field, rbrace token.Position, is_interface bool) {
P.state = opening_scope;
P.separator = blank;
P.Token(lbrace, token.LBRACE);
if len(list) > 0 {
P.newlines = 1;
for i, fld := range list {
if i > 0 {
P.separator = semicolon;
P.newlines = 1;
}
n := P.Idents(fld.Names, P.full);
if n > 0 {
// at least one identifier
P.separator = tab
};
if n > 0 || len(fld.Names) == 0 {
// at least one identifier or anonymous field
if is_interface {
if ftyp, is_ftyp := fld.Type.(*ast.FuncType); is_ftyp {
P.Signature(ftyp.Params, ftyp.Results);
} else {
P.Expr(fld.Type);
}
} else {
P.Expr(fld.Type);
if fld.Tag != nil {
P.separator = tab;
P.Expr(&ast.StringList{fld.Tag});
}
}
}
}
P.newlines = 1;
}
P.state = closing_scope;
P.Token(rbrace, token.RBRACE);
P.opt_semi = true;
}
// ----------------------------------------------------------------------------
// Expressions
func (P *Printer) Expr1(x ast.Expr, prec1 int)
func (P *Printer) Stmt(s ast.Stmt)
func (P *Printer) DoBadExpr(x *ast.BadExpr) {
P.String(noPos, "BadExpr");
}
func (P *Printer) DoIdent(x *ast.Ident) {
P.HtmlIdentifier(x);
}
func (P *Printer) DoBinaryExpr(x *ast.BinaryExpr) {
prec := x.Op.Precedence();
if prec < P.prec {
P.Token(noPos, token.LPAREN);
}
P.Expr1(x.X, prec);
P.separator = blank;
P.Token(x.OpPos, x.Op);
P.separator = blank;
P.Expr1(x.Y, prec);
if prec < P.prec {
P.Token(noPos, token.RPAREN);
}
}
func (P *Printer) DoKeyValueExpr(x *ast.KeyValueExpr) {
P.Expr(x.Key);
P.separator = blank;
P.Token(x.Colon, token.COLON);
P.separator = blank;
P.Expr(x.Value);
}
func (P *Printer) DoStarExpr(x *ast.StarExpr) {
P.Token(x.Pos(), token.MUL);
P.Expr(x.X);
}
func (P *Printer) DoUnaryExpr(x *ast.UnaryExpr) {
prec := token.UnaryPrec;
if prec < P.prec {
P.Token(noPos, token.LPAREN);
}
P.Token(x.Pos(), x.Op);
if x.Op == token.RANGE {
P.separator = blank;
}
P.Expr1(x.X, prec);
if prec < P.prec {
P.Token(noPos, token.RPAREN);
}
}
func (P *Printer) DoIntLit(x *ast.IntLit) {
// TODO get rid of string conversion here
P.String(x.Pos(), string(x.Value));
}
func (P *Printer) DoFloatLit(x *ast.FloatLit) {
// TODO get rid of string conversion here
P.String(x.Pos(), string(x.Value));
}
func (P *Printer) DoCharLit(x *ast.CharLit) {
// TODO get rid of string conversion here
P.String(x.Pos(), string(x.Value));
}
func (P *Printer) DoStringLit(x *ast.StringLit) {
// TODO get rid of string conversion here
P.String(x.Pos(), string(x.Value));
}
func (P *Printer) DoStringList(x *ast.StringList) {
for i, x := range x.Strings {
if i > 0 {
P.separator = blank;
}
P.DoStringLit(x);
}
}
func (P *Printer) DoFuncType(x *ast.FuncType)
func (P *Printer) DoFuncLit(x *ast.FuncLit) {
P.DoFuncType(x.Type);
P.separator = blank;
P.Stmt(x.Body);
P.opt_semi = false; // BUG 6g or spec
P.newlines = 0;
}
func (P *Printer) DoParenExpr(x *ast.ParenExpr) {
P.Token(x.Pos(), token.LPAREN);
P.Expr(x.X);
P.Token(x.Rparen, token.RPAREN);
}
func (P *Printer) DoSelectorExpr(x *ast.SelectorExpr) {
P.Expr1(x.X, token.HighestPrec);
P.Token(noPos, token.PERIOD);
P.Expr1(x.Sel, token.HighestPrec);
}
func (P *Printer) DoTypeAssertExpr(x *ast.TypeAssertExpr) {
P.Expr1(x.X, token.HighestPrec);
P.Token(noPos, token.PERIOD);
P.Token(noPos, token.LPAREN);
P.Expr(x.Type);
P.Token(noPos, token.RPAREN);
}
func (P *Printer) DoIndexExpr(x *ast.IndexExpr) {
P.Expr1(x.X, token.HighestPrec);
P.Token(noPos, token.LBRACK);
P.Expr(x.Index);
P.Token(noPos, token.RBRACK);
}
func (P *Printer) DoSliceExpr(x *ast.SliceExpr) {
P.Expr1(x.X, token.HighestPrec);
P.Token(noPos, token.LBRACK);
P.Expr(x.Begin);
P.Token(noPos, token.COLON);
P.Expr(x.End);
P.Token(noPos, token.RBRACK);
}
func (P *Printer) DoCallExpr(x *ast.CallExpr) {
P.Expr1(x.Fun, token.HighestPrec);
P.Token(x.Lparen, token.LPAREN);
P.Exprs(x.Args);
P.Token(x.Rparen, token.RPAREN);
}
func (P *Printer) DoCompositeLit(x *ast.CompositeLit) {
P.Expr1(x.Type, token.HighestPrec);
P.Token(x.Lbrace, token.LBRACE);
P.Exprs(x.Elts);
P.Token(x.Rbrace, token.RBRACE);
}
func (P *Printer) DoEllipsis(x *ast.Ellipsis) {
P.Token(x.Pos(), token.ELLIPSIS);
}
func (P *Printer) DoArrayType(x *ast.ArrayType) {
P.Token(x.Pos(), token.LBRACK);
P.Expr(x.Len);
P.Token(noPos, token.RBRACK);
P.Expr(x.Elt);
}
func (P *Printer) DoSliceType(x *ast.SliceType) {
P.Token(x.Pos(), token.LBRACK);
P.Token(noPos, token.RBRACK);
P.Expr(x.Elt);
}
func (P *Printer) DoStructType(x *ast.StructType) {
P.Token(x.Pos(), token.STRUCT);
if x.Fields != nil {
P.Fields(x.Lbrace, x.Fields, x.Rbrace, false);
}
}
func (P *Printer) DoFuncType(x *ast.FuncType) {
P.Token(x.Pos(), token.FUNC);
P.Signature(x.Params, x.Results);
}
func (P *Printer) DoInterfaceType(x *ast.InterfaceType) {
P.Token(x.Pos(), token.INTERFACE);
if x.Methods != nil {
P.Fields(x.Lbrace, x.Methods, x.Rbrace, true);
}
}
func (P *Printer) DoMapType(x *ast.MapType) {
P.Token(x.Pos(), token.MAP);
P.separator = blank;
P.Token(noPos, token.LBRACK);
P.Expr(x.Key);
P.Token(noPos, token.RBRACK);
P.Expr(x.Value);
}
func (P *Printer) DoChanType(x *ast.ChanType) {
switch x.Dir {
case ast.SEND | ast.RECV:
P.Token(x.Pos(), token.CHAN);
case ast.RECV:
P.Token(x.Pos(), token.ARROW);
P.Token(noPos, token.CHAN);
case ast.SEND:
P.Token(x.Pos(), token.CHAN);
P.separator = blank;
P.Token(noPos, token.ARROW);
}
P.separator = blank;
P.Expr(x.Value);
}
func (P *Printer) Expr1(x ast.Expr, prec1 int) {
if x == nil {
return; // empty expression list
}
saved_prec := P.prec;
P.prec = prec1;
x.Visit(P);
P.prec = saved_prec;
}
func (P *Printer) Expr(x ast.Expr) {
P.Expr1(x, token.LowestPrec);
}
// ----------------------------------------------------------------------------
// Statements
func (P *Printer) Stmt(s ast.Stmt) {
s.Visit(P);
}
func (P *Printer) DoBadStmt(s *ast.BadStmt) {
panic();
}
func (P *Printer) Decl(d ast.Decl);
func (P *Printer) DoDeclStmt(s *ast.DeclStmt) {
P.Decl(s.Decl);
}
func (P *Printer) DoEmptyStmt(s *ast.EmptyStmt) {
P.String(s.Pos(), "");
}
func (P *Printer) DoLabeledStmt(s *ast.LabeledStmt) {
P.indentation--;
P.Expr(s.Label);
P.Token(noPos, token.COLON);
P.indentation++;
// TODO be more clever if s.Stmt is a labeled stat as well
P.separator = tab;
P.Stmt(s.Stmt);
}
func (P *Printer) DoExprStmt(s *ast.ExprStmt) {
P.Expr(s.X);
}
func (P *Printer) DoIncDecStmt(s *ast.IncDecStmt) {
P.Expr(s.X);
P.Token(noPos, s.Tok);
}
func (P *Printer) DoAssignStmt(s *ast.AssignStmt) {
P.Exprs(s.Lhs);
P.separator = blank;
P.Token(s.TokPos, s.Tok);
P.separator = blank;
P.Exprs(s.Rhs);
}
func (P *Printer) DoGoStmt(s *ast.GoStmt) {
P.Token(s.Pos(), token.GO);
P.separator = blank;
P.Expr(s.Call);
}
func (P *Printer) DoDeferStmt(s *ast.DeferStmt) {
P.Token(s.Pos(), token.DEFER);
P.separator = blank;
P.Expr(s.Call);
}
func (P *Printer) DoReturnStmt(s *ast.ReturnStmt) {
P.Token(s.Pos(), token.RETURN);
P.separator = blank;
P.Exprs(s.Results);
}
func (P *Printer) DoBranchStmt(s *ast.BranchStmt) {
P.Token(s.Pos(), s.Tok);
if s.Label != nil {
P.separator = blank;
P.Expr(s.Label);
}
}
func (P *Printer) StatementList(list []ast.Stmt) {
if list != nil {
for i, s := range list {
if i == 0 {
P.newlines = 1;
} else { // i > 0
if !P.opt_semi || *optsemicolons {
// semicolon is required
P.separator = semicolon;
}
}
P.Stmt(s);
P.newlines = 1;
P.state = inside_list;
}
}
}
/*
func (P *Printer) Block(list []ast.Stmt, indent bool) {
P.state = opening_scope;
P.Token(b.Pos_, b.Tok);
if !indent {
P.indentation--;
}
P.StatementList(b.List);
if !indent {
P.indentation++;
}
if !*optsemicolons {
P.separator = none;
}
P.state = closing_scope;
if b.Tok == token.LBRACE {
P.Token(b.Rbrace, token.RBRACE);
P.opt_semi = true;
} else {
P.String(noPos, ""); // process closing_scope state transition!
}
}
*/
func (P *Printer) DoBlockStmt(s *ast.BlockStmt) {
P.state = opening_scope;
P.Token(s.Pos(), token.LBRACE);
P.StatementList(s.List);
if !*optsemicolons {
P.separator = none;
}
P.state = closing_scope;
P.Token(s.Rbrace, token.RBRACE);
P.opt_semi = true;
}
func (P *Printer) ControlClause(isForStmt bool, init ast.Stmt, expr ast.Expr, post ast.Stmt) {
P.separator = blank;
if init == nil && post == nil {
// no semicolons required
if expr != nil {
P.Expr(expr);
}
} else {
// all semicolons required
// (they are not separators, print them explicitly)
if init != nil {
P.Stmt(init);
P.separator = none;
}
P.Token(noPos, token.SEMICOLON);
P.separator = blank;
if expr != nil {
P.Expr(expr);
P.separator = none;
}
if isForStmt {
P.Token(noPos, token.SEMICOLON);
P.separator = blank;
if post != nil {
P.Stmt(post);
}
}
}
P.separator = blank;
}
func (P *Printer) DoIfStmt(s *ast.IfStmt) {
P.Token(s.Pos(), token.IF);
P.ControlClause(false, s.Init, s.Cond, nil);
P.Stmt(s.Body);
if s.Else != nil {
P.separator = blank;
P.Token(noPos, token.ELSE);
P.separator = blank;
P.Stmt(s.Else);
}
}
func (P *Printer) DoCaseClause(s *ast.CaseClause) {
if s.Values != nil {
P.Token(s.Pos(), token.CASE);
P.separator = blank;
P.Exprs(s.Values);
} else {
P.Token(s.Pos(), token.DEFAULT);
}
P.Token(s.Colon, token.COLON);
P.indentation++;
P.StatementList(s.Body);
P.indentation--;
P.newlines = 1;
}
func (P *Printer) DoSwitchStmt(s *ast.SwitchStmt) {
P.Token(s.Pos(), token.SWITCH);
P.ControlClause(false, s.Init, s.Tag, nil);
P.Stmt(s.Body);
}
func (P *Printer) DoTypeCaseClause(s *ast.TypeCaseClause) {
if s.Type != nil {
P.Token(s.Pos(), token.CASE);
P.separator = blank;
P.Expr(s.Type);
} else {
P.Token(s.Pos(), token.DEFAULT);
}
P.Token(s.Colon, token.COLON);
P.indentation++;
P.StatementList(s.Body);
P.indentation--;
P.newlines = 1;
}
func (P *Printer) DoTypeSwitchStmt(s *ast.TypeSwitchStmt) {
P.Token(s.Pos(), token.SWITCH);
P.separator = blank;
if s.Init != nil {
P.Stmt(s.Init);
P.separator = none;
P.Token(noPos, token.SEMICOLON);
}
P.separator = blank;
P.Stmt(s.Assign);
P.separator = blank;
P.Stmt(s.Body);
}
func (P *Printer) DoCommClause(s *ast.CommClause) {
if s.Rhs != nil {
P.Token(s.Pos(), token.CASE);
P.separator = blank;
if s.Lhs != nil {
P.Expr(s.Lhs);
P.separator = blank;
P.Token(noPos, s.Tok);
P.separator = blank;
}
P.Expr(s.Rhs);
} else {
P.Token(s.Pos(), token.DEFAULT);
}
P.Token(s.Colon, token.COLON);
P.indentation++;
P.StatementList(s.Body);
P.indentation--;
P.newlines = 1;
}
func (P *Printer) DoSelectStmt(s *ast.SelectStmt) {
P.Token(s.Pos(), token.SELECT);
P.separator = blank;
P.Stmt(s.Body);
}
func (P *Printer) DoForStmt(s *ast.ForStmt) {
P.Token(s.Pos(), token.FOR);
P.ControlClause(true, s.Init, s.Cond, s.Post);
P.Stmt(s.Body);
}
func (P *Printer) DoRangeStmt(s *ast.RangeStmt) {
P.Token(s.Pos(), token.FOR);
P.separator = blank;
P.Expr(s.Key);
if s.Value != nil {
P.Token(noPos, token.COMMA);
P.separator = blank;
P.state = inside_list;
P.Expr(s.Value);
}
P.separator = blank;
P.Token(s.TokPos, s.Tok);
P.separator = blank;
P.Token(noPos, token.RANGE);
P.separator = blank;
P.Expr(s.X);
P.separator = blank;
P.Stmt(s.Body);
}
// ----------------------------------------------------------------------------
// Declarations
func (P *Printer) DoBadDecl(d *ast.BadDecl) {
P.String(d.Pos(), "<BAD DECL>");
}
func (P *Printer) importSpec(d *ast.ImportSpec) {
if d.Name != nil {
P.Expr(d.Name);
} else {
P.String(d.Path[0].Pos(), ""); // flush pending ';' separator/newlines
}
P.separator = tab;
// TODO fix for longer package names
P.HtmlPackageName(d.Path[0].Pos(), string(d.Path[0].Value));
P.newlines = 2;
}
func (P *Printer) valueSpec(d *ast.ValueSpec) {
P.Idents(d.Names, P.full);
if d.Type != nil {
P.separator = blank; // TODO switch to tab? (indentation problem with structs)
P.Expr(d.Type);
}
if d.Values != nil {
P.separator = tab;
P.Token(noPos, token.ASSIGN);
P.separator = blank;
P.Exprs(d.Values);
}
P.newlines = 2;
}
func (P *Printer) typeSpec(d *ast.TypeSpec) {
P.Expr(d.Name);
P.separator = blank; // TODO switch to tab? (but indentation problem with structs)
P.Expr(d.Type);
P.newlines = 2;
}
func (P *Printer) spec(d ast.Spec) {
switch s := d.(type) {
case *ast.ImportSpec: P.importSpec(s);
case *ast.ValueSpec: P.valueSpec(s);
case *ast.TypeSpec: P.typeSpec(s);
default: panic("unreachable");
}
}
func (P *Printer) DoGenDecl(d *ast.GenDecl) {
P.Token(d.Pos(), d.Tok);
P.separator = blank;
if d.Lparen.Line > 0 {
// group of parenthesized declarations
P.state = opening_scope;
P.Token(d.Lparen, token.LPAREN);
if len(d.Specs) > 0 {
P.newlines = 1;
for i := 0; i < len(d.Specs); i++ {
if i > 0 {
P.separator = semicolon;
}
P.spec(d.Specs[i]);
P.newlines = 1;
}
}
P.state = closing_scope;
P.Token(d.Rparen, token.RPAREN);
P.opt_semi = true;
P.newlines = 2;
} else {
// single declaration
P.spec(d.Specs[0]);
}
}
func (P *Printer) DoFuncDecl(d *ast.FuncDecl) {
P.Token(d.Pos(), token.FUNC);
P.separator = blank;
if recv := d.Recv; recv != nil {
// method: print receiver
P.Token(noPos, token.LPAREN);
if len(recv.Names) > 0 {
P.Expr(recv.Names[0]);
P.separator = blank;
}
P.Expr(recv.Type);
P.Token(noPos, token.RPAREN);
P.separator = blank;
}
P.Expr(d.Name);
P.Signature(d.Type.Params, d.Type.Results);
if P.full && d.Body != nil {
P.separator = blank;
P.Stmt(d.Body);
}
P.newlines = 3;
}
func (P *Printer) Decl(d ast.Decl) {
d.Visit(P);
}
// ----------------------------------------------------------------------------
// Program
func (P *Printer) DoProgram(p *ast.Program) {
P.full = true;
P.Token(p.Pos(), token.PACKAGE);
P.separator = blank;
P.Expr(p.Name);
P.newlines = 1;
for i := 0; i < len(p.Decls); i++ {
P.Decl(p.Decls[i]);
}
P.newlines = 1;
}