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authorRobert Griesemer <gri@golang.org>2010-02-19 16:01:31 -0800
committerRobert Griesemer <gri@golang.org>2010-02-19 16:01:31 -0800
commit8e714aab2bfdc71635786732e1bac45f27f2201c (patch)
tree48e559907b9f5b7d677d05c93678edc6f0c6f61c
parentcf743c1be66da7109da783c88a9eb3f851f52db3 (diff)
downloadgo-8e714aab2bfdc71635786732e1bac45f27f2201c.tar.gz
go-8e714aab2bfdc71635786732e1bac45f27f2201c.zip
- removed exp/parser (support for old semicolon syntax)
- go/ast: removed StringList (not needed anymore) - go/ast: changed import path and field list tag to a single string - updated all dependencies R=rsc CC=golang-dev https://golang.org/cl/217056
-rw-r--r--src/cmd/cgo/ast.go5
-rw-r--r--src/cmd/godoc/index.go8
-rw-r--r--src/cmd/gofmt/doc.go8
-rw-r--r--src/cmd/gofmt/gofmt.go18
-rw-r--r--src/pkg/Makefile1
-rw-r--r--src/pkg/exp/eval/eval_test.go2
-rw-r--r--src/pkg/exp/eval/expr.go14
-rw-r--r--src/pkg/exp/eval/expr_test.go3
-rw-r--r--src/pkg/exp/eval/stmt_test.go16
-rw-r--r--src/pkg/exp/eval/world.go6
-rw-r--r--src/pkg/exp/parser/Makefile12
-rw-r--r--src/pkg/exp/parser/interface.go203
-rw-r--r--src/pkg/exp/parser/parser.go1972
-rw-r--r--src/pkg/exp/parser/parser_test.go95
-rw-r--r--src/pkg/go/ast/ast.go19
-rw-r--r--src/pkg/go/ast/walk.go13
-rw-r--r--src/pkg/go/parser/parser.go11
-rw-r--r--src/pkg/go/printer/nodes.go9
18 files changed, 33 insertions, 2382 deletions
diff --git a/src/cmd/cgo/ast.go b/src/cmd/cgo/ast.go
index f6142d135d..2cc771e16f 100644
--- a/src/cmd/cgo/ast.go
+++ b/src/cmd/cgo/ast.go
@@ -90,14 +90,14 @@ func openProg(name string, p *Prog) {
ws := 0
for _, spec := range d.Specs {
s, ok := spec.(*ast.ImportSpec)
- if !ok || len(s.Path) != 1 || string(s.Path[0].Value) != `"C"` {
+ if !ok || string(s.Path.Value) != `"C"` {
d.Specs[ws] = spec
ws++
continue
}
sawC = true
if s.Name != nil {
- error(s.Path[0].Pos(), `cannot rename import "C"`)
+ error(s.Path.Pos(), `cannot rename import "C"`)
}
if s.Doc != nil {
p.Preamble += doc.CommentText(s.Doc) + "\n"
@@ -168,7 +168,6 @@ func walk(x interface{}, p *Prog, context string) {
case *ast.Ident:
case *ast.Ellipsis:
case *ast.BasicLit:
- case *ast.StringList:
case *ast.FuncLit:
walk(n.Type, p, "type")
walk(n.Body, p, "stmt")
diff --git a/src/cmd/godoc/index.go b/src/cmd/godoc/index.go
index 14aacfec68..dcad67a95a 100644
--- a/src/cmd/godoc/index.go
+++ b/src/cmd/godoc/index.go
@@ -479,9 +479,7 @@ func (x *Indexer) visitSpec(spec ast.Spec, isVarDecl bool) {
case *ast.ImportSpec:
x.visitComment(n.Doc)
x.visitIdent(ImportDecl, n.Name)
- for _, s := range n.Path {
- ast.Walk(x, s)
- }
+ ast.Walk(x, n.Path)
x.visitComment(n.Comment)
case *ast.ValueSpec:
@@ -524,9 +522,7 @@ func (x *Indexer) Visit(node interface{}) ast.Visitor {
x.visitIdent(VarDecl, m)
}
ast.Walk(x, n.Type)
- for _, s := range n.Tag {
- ast.Walk(x, s)
- }
+ ast.Walk(x, n.Tag)
x.visitComment(n.Comment)
case *ast.DeclStmt:
diff --git a/src/cmd/gofmt/doc.go b/src/cmd/gofmt/doc.go
index e9b1d6c47f..4b4adba030 100644
--- a/src/cmd/gofmt/doc.go
+++ b/src/cmd/gofmt/doc.go
@@ -29,14 +29,6 @@ The flags are:
-tabwidth=8
tab width in spaces.
-Flags to aid the transition to the new semicolon-free syntax (these flags will be
-removed eventually):
-
- -oldparser=true
- parse old syntax (required semicolons).
- -oldprinter=true
- print old syntax (required semicolons).
-
Debugging flags:
-trace
diff --git a/src/cmd/gofmt/gofmt.go b/src/cmd/gofmt/gofmt.go
index 6997bf3e21..abd30edc89 100644
--- a/src/cmd/gofmt/gofmt.go
+++ b/src/cmd/gofmt/gofmt.go
@@ -6,7 +6,6 @@ package main
import (
"bytes"
- oldParser "exp/parser"
"flag"
"fmt"
"go/ast"
@@ -35,9 +34,6 @@ var (
tabWidth = flag.Int("tabwidth", 8, "tab width")
tabIndent = flag.Bool("tabindent", true, "indent with tabs independent of -spaces")
useSpaces = flag.Bool("spaces", true, "align with spaces instead of tabs")
-
- // semicolon transition
- useOldParser = flag.Bool("oldparser", false, "parse old syntax (required semicolons)")
)
@@ -96,16 +92,12 @@ func processFile(f *os.File) os.Error {
return err
}
- var file *ast.File
- if *useOldParser {
- file, err = oldParser.ParseFile(f.Name(), src, parserMode)
- } else {
- var scope *ast.Scope
- if *debug {
- scope = ast.NewScope(nil)
- }
- file, err = parser.ParseFile(f.Name(), src, scope, parserMode)
+ var scope *ast.Scope
+ if *debug {
+ scope = ast.NewScope(nil)
}
+ file, err := parser.ParseFile(f.Name(), src, scope, parserMode)
+
if err != nil {
return err
}
diff --git a/src/pkg/Makefile b/src/pkg/Makefile
index 2a65d37698..7fb0240a54 100644
--- a/src/pkg/Makefile
+++ b/src/pkg/Makefile
@@ -64,7 +64,6 @@ DIRS=\
exp/eval\
exp/exception\
exp/iterable\
- exp/parser\
expvar\
flag\
fmt\
diff --git a/src/pkg/exp/eval/eval_test.go b/src/pkg/exp/eval/eval_test.go
index 93a643b5aa..911c7e4a52 100644
--- a/src/pkg/exp/eval/eval_test.go
+++ b/src/pkg/exp/eval/eval_test.go
@@ -43,7 +43,7 @@ func runTests(t *testing.T, baseName string, tests []test) {
func (a test) run(t *testing.T, name string) {
w := newTestWorld()
for _, j := range a {
- src := j.code
+ src := j.code + ";" // trailing semicolon to finish statement
if noisy {
println("code:", src)
}
diff --git a/src/pkg/exp/eval/expr.go b/src/pkg/exp/eval/expr.go
index ed32c0a3c6..94714943c6 100644
--- a/src/pkg/exp/eval/expr.go
+++ b/src/pkg/exp/eval/expr.go
@@ -627,20 +627,6 @@ func (a *exprCompiler) compile(x ast.Expr, callCtx bool) *expr {
}
return ei.compileStarExpr(v)
- case *ast.StringList:
- strings := make([]*expr, len(x.Strings))
- bad := false
- for i, s := range x.Strings {
- strings[i] = a.compile(s, false)
- if strings[i] == nil {
- bad = true
- }
- }
- if bad {
- return nil
- }
- return ei.compileStringList(strings)
-
case *ast.StructType:
goto notimpl
diff --git a/src/pkg/exp/eval/expr_test.go b/src/pkg/exp/eval/expr_test.go
index 5cfbc82327..10c7f6be52 100644
--- a/src/pkg/exp/eval/expr_test.go
+++ b/src/pkg/exp/eval/expr_test.go
@@ -51,9 +51,6 @@ var exprTests = []test{
CErr("\"\\z\"", illegalEscape),
CErr("\"abc", "string not terminated"),
- Val("\"abc\" \"def\"", "abcdef"),
- CErr("\"abc\" \"\\z\"", illegalEscape),
-
Val("(i)", 1),
Val("ai[0]", 1),
diff --git a/src/pkg/exp/eval/stmt_test.go b/src/pkg/exp/eval/stmt_test.go
index 1600a75078..a14a288d93 100644
--- a/src/pkg/exp/eval/stmt_test.go
+++ b/src/pkg/exp/eval/stmt_test.go
@@ -202,8 +202,8 @@ var stmtTests = []test{
Run("fn1 := func() int { L: goto L; i = 2 }"),
Run("fn1 := func() int { return 1; L: goto L }"),
// Scope checking
- Run("fn1 := func() { { L: x:=1 } goto L }"),
- CErr("fn1 := func() { { x:=1; L: } goto L }", "into scope"),
+ Run("fn1 := func() { { L: x:=1 }; goto L }"),
+ CErr("fn1 := func() { { x:=1; L: }; goto L }", "into scope"),
CErr("fn1 := func() { goto L; x:=1; L: }", "into scope"),
Run("fn1 := func() { goto L; { L: x:=1 } }"),
CErr("fn1 := func() { goto L; { x:=1; L: } }", "into scope"),
@@ -279,10 +279,10 @@ var stmtTests = []test{
// Scoping
Val2("for i := 2; true; { i2 = i; i := 3; break }", "i", 1, "i2", 2),
// Labeled break/continue
- Val1("L1: for { L2: for { i+=2; break L1; i+=4 } i+=8 }", "i", 1+2),
- Val1("L1: for { L2: for { i+=2; break L2; i+=4 } i+=8; break; i+=16 }", "i", 1+2+8),
+ Val1("L1: for { L2: for { i+=2; break L1; i+=4 }; i+=8 }", "i", 1+2),
+ Val1("L1: for { L2: for { i+=2; break L2; i+=4 }; i+=8; break; i+=16 }", "i", 1+2+8),
CErr("L1: { for { break L1 } }", "break.*not defined"),
- CErr("L1: for {} for { break L1 }", "break.*not defined"),
+ CErr("L1: for {}; for { break L1 }", "break.*not defined"),
CErr("L1:; for { break L1 }", "break.*not defined"),
Val2("L1: for i = 0; i < 2; i++ { L2: for { i2++; continue L1; i2++ } }", "i", 2, "i2", 4),
CErr("L1: { for { continue L1 } }", "continue.*not defined"),
@@ -294,7 +294,7 @@ var stmtTests = []test{
CErr("fn1 := func() int{ for {break} }", "return"),
Run("fn1 := func() int{ for { for {break} } }"),
CErr("fn1 := func() int{ L1: for { for {break L1} } }", "return"),
- Run("fn1 := func() int{ for true {} return 1 }"),
+ Run("fn1 := func() int{ for true {}; return 1 }"),
// Selectors
Val1("var x struct { a int; b int }; x.a = 42; i = x.a", "i", 42),
@@ -305,7 +305,7 @@ var stmtTests = []test{
CErr("type T struct { x int }; type U struct { x int }; var y struct { T; U }; y.x = 42", "ambiguous.*\tT\\.x\n\tU\\.x"),
CErr("type T struct { *T }; var x T; x.foo", "no field"),
- Val1("fib := func(int) int{return 0;}; fib = func(v int) int { if v < 2 { return 1 } return fib(v-1)+fib(v-2) }; i = fib(20)", "i", 10946),
+ Val1("fib := func(int) int{return 0;}; fib = func(v int) int { if v < 2 { return 1 }; return fib(v-1)+fib(v-2) }; i = fib(20)", "i", 10946),
// Make slice
Val2("x := make([]int, 2); x[0] = 42; i, i2 = x[0], x[1]", "i", 42, "i2", 0),
@@ -335,7 +335,7 @@ var stmtTests = []test{
RErr("x := make(map[int] int); i = x[1]", "key '1' not found"),
// Functions
- Val2("func fib(n int) int { if n <= 2 { return n } return fib(n-1) + fib(n-2) }", "fib(4)", 5, "fib(10)", 89),
+ Val2("func fib(n int) int { if n <= 2 { return n }; return fib(n-1) + fib(n-2) }", "fib(4)", 5, "fib(10)", 89),
Run("func f1(){}"),
Run2("func f1(){}", "f1()"),
}
diff --git a/src/pkg/exp/eval/world.go b/src/pkg/exp/eval/world.go
index c36081b263..1d19b50b62 100644
--- a/src/pkg/exp/eval/world.go
+++ b/src/pkg/exp/eval/world.go
@@ -9,7 +9,7 @@ package eval
import (
"go/ast"
- parser "exp/parser"
+ "go/parser"
"go/scanner"
"go/token"
"os"
@@ -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)
+ stmts, err := parser.ParseStmtList("input", text, nil)
if err == nil {
return w.CompileStmtList(stmts)
}
// Otherwise try as DeclList.
- decls, err1 := parser.ParseDeclList("input", text)
+ decls, err1 := parser.ParseDeclList("input", text, nil)
if err1 == nil {
return w.CompileDeclList(decls)
}
diff --git a/src/pkg/exp/parser/Makefile b/src/pkg/exp/parser/Makefile
deleted file mode 100644
index da35917585..0000000000
--- a/src/pkg/exp/parser/Makefile
+++ /dev/null
@@ -1,12 +0,0 @@
-# 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.
-
-include ../../../Make.$(GOARCH)
-
-TARG=exp/parser
-GOFILES=\
- interface.go\
- parser.go\
-
-include ../../../Make.pkg
diff --git a/src/pkg/exp/parser/interface.go b/src/pkg/exp/parser/interface.go
deleted file mode 100644
index e04ff18887..0000000000
--- a/src/pkg/exp/parser/interface.go
+++ /dev/null
@@ -1,203 +0,0 @@
-// 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.
-
-// This file contains the exported entry points for invoking the parser.
-
-package oldParser
-
-import (
- "bytes"
- "fmt"
- "go/ast"
- "go/scanner"
- "io"
- "io/ioutil"
- "os"
- pathutil "path"
- "strings"
-)
-
-
-// If src != nil, readSource converts src to a []byte if possible;
-// otherwise it returns an error. If src == nil, readSource returns
-// the result of reading the file specified by filename.
-//
-func readSource(filename string, src interface{}) ([]byte, os.Error) {
- if src != nil {
- switch s := src.(type) {
- case string:
- return strings.Bytes(s), nil
- case []byte:
- return s, nil
- case *bytes.Buffer:
- // is io.Reader, but src is already available in []byte form
- if s != nil {
- return s.Bytes(), nil
- }
- case io.Reader:
- var buf bytes.Buffer
- _, err := io.Copy(&buf, s)
- if err != nil {
- return nil, err
- }
- return buf.Bytes(), nil
- default:
- return nil, os.ErrorString("invalid source")
- }
- }
-
- return ioutil.ReadFile(filename)
-}
-
-
-// ParseExpr parses a Go expression and returns the corresponding
-// 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{}) (ast.Expr, os.Error) {
- data, err := readSource(filename, src)
- if err != nil {
- return nil, err
- }
-
- var p parser
- p.init(filename, data, 0)
- return p.parseExpr(), p.GetError(scanner.Sorted)
-}
-
-
-// ParseStmtList parses a list of Go statements and returns the list
-// 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{}) ([]ast.Stmt, os.Error) {
- data, err := readSource(filename, src)
- if err != nil {
- return nil, err
- }
-
- var p parser
- p.init(filename, data, 0)
- return p.parseStmtList(), p.GetError(scanner.Sorted)
-}
-
-
-// ParseDeclList parses a list of Go declarations and returns the list
-// 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{}) ([]ast.Decl, os.Error) {
- data, err := readSource(filename, src)
- if err != nil {
- return nil, err
- }
-
- var p parser
- p.init(filename, data, 0)
- return p.parseDeclList(), p.GetError(scanner.Sorted)
-}
-
-
-// ParseFile parses a Go source file and returns a File node.
-//
-// If src != nil, ParseFile parses the file source from src. src may
-// be provided in a variety of formats. At the moment the following types
-// are supported: string, []byte, and io.Reader. In this case, filename is
-// only used for source position information and error messages.
-//
-// If src == nil, ParseFile parses the file specified by filename.
-//
-// The mode parameter controls the amount of source text parsed and other
-// optional parser functionality.
-//
-// If the source couldn't be read, the returned AST is nil and the error
-// indicates the specific failure. If the source was read but syntax
-// errors were found, the result is a partial AST (with ast.BadX nodes
-// 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{}, mode uint) (*ast.File, os.Error) {
- data, err := readSource(filename, src)
- if err != nil {
- return nil, err
- }
-
- var p parser
- p.init(filename, data, mode)
- return p.parseFile(), p.GetError(scanner.NoMultiples)
-}
-
-
-// ParsePkgFile parses the file specified by filename and returns the
-// corresponding AST. If the file cannot be read, has syntax errors, or
-// does not belong to the package (i.e., pkgname != "" and the package
-// name in the file doesn't match pkkname), an error is returned.
-//
-func ParsePkgFile(pkgname, filename string, mode uint) (*ast.File, os.Error) {
- src, err := ioutil.ReadFile(filename)
- if err != nil {
- return nil, err
- }
-
- if pkgname != "" {
- prog, err := ParseFile(filename, src, PackageClauseOnly)
- if err != nil {
- return nil, err
- }
- if prog.Name.Name() != pkgname {
- return nil, os.NewError(fmt.Sprintf("multiple packages found: %s, %s", prog.Name.Name(), pkgname))
- }
- if mode == PackageClauseOnly {
- return prog, nil
- }
- }
-
- return ParseFile(filename, src, mode)
-}
-
-
-// ParsePackage parses all files in the directory specified by path and
-// returns an AST representing the package found. The set of files may be
-// restricted by providing a non-nil filter function; only the files with
-// os.Dir entries passing through the filter are considered.
-// If ParsePackage does not find exactly one package, it returns an error.
-//
-func ParsePackage(path string, filter func(*os.Dir) bool, mode uint) (*ast.Package, os.Error) {
- fd, err := os.Open(path, os.O_RDONLY, 0)
- if err != nil {
- return nil, err
- }
- defer fd.Close()
-
- list, err := fd.Readdir(-1)
- if err != nil {
- return nil, err
- }
-
- name := ""
- files := make(map[string]*ast.File)
- for i := 0; i < len(list); i++ {
- entry := &list[i]
- if filter == nil || filter(entry) {
- filename := pathutil.Join(path, entry.Name)
- src, err := ParsePkgFile(name, filename, mode)
- if err != nil {
- return nil, err
- }
- files[filename] = src
- if name == "" {
- name = src.Name.Name()
- }
- }
- }
-
- if len(files) == 0 {
- return nil, os.NewError(path + ": no package found")
- }
-
- return &ast.Package{name, nil, files}, nil
-}
diff --git a/src/pkg/exp/parser/parser.go b/src/pkg/exp/parser/parser.go
deleted file mode 100644
index 6114c88953..0000000000
--- a/src/pkg/exp/parser/parser.go
+++ /dev/null
@@ -1,1972 +0,0 @@
-// 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.
-
-// A parser for "old" Go source files using the old semicolon syntax.
-// Input may be provided in a variety of forms (see the various Parse*
-// functions); the output is an abstract syntax tree (AST) representing
-// the Go source. The oldParser is invoked through one of the Parse*
-// functions.
-//
-// NOTE: This package is deprecated and will be removed once all Go code
-// has been converted to using the new syntax and after a reasonable
-// grace period.
-//
-package oldParser
-
-import (
- "container/vector"
- "fmt"
- "go/ast"
- "go/scanner"
- "go/token"
-)
-
-
-// noPos is used when there is no corresponding source position for a token.
-var noPos token.Position
-
-
-// The mode parameter to the Parse* functions is a set of flags (or 0).
-// They control the amount of source code parsed and other optional
-// parser functionality.
-//
-const (
- PackageClauseOnly uint = 1 << iota // parsing stops after package clause
- ImportsOnly // parsing stops after import declarations
- ParseComments // parse comments and add them to AST
- Trace // print a trace of parsed productions
-)
-
-
-// The parser structure holds the parser's internal state.
-type parser struct {
- scanner.ErrorVector
- scanner scanner.Scanner
-
- // Tracing/debugging
- mode uint // parsing mode
- trace bool // == (mode & Trace != 0)
- indent uint // indentation used for tracing output
-
- // Comments
- comments *ast.CommentGroup // list of collected comments
- lastComment *ast.CommentGroup // last comment in the comments list
- leadComment *ast.CommentGroup // the last lead comment
- lineComment *ast.CommentGroup // the last line comment
-
- // Next token
- pos token.Position // token position
- tok token.Token // one token look-ahead
- lit []byte // token literal
-
- // Non-syntactic parser control
- optSemi bool // true if semicolon separator is optional in statement list
- exprLev int // < 0: in control clause, >= 0: in expression
-
- // Scopes
- pkgScope *ast.Scope
- fileScope *ast.Scope
- topScope *ast.Scope
-}
-
-
-// scannerMode returns the scanner mode bits given the parser's mode bits.
-func scannerMode(mode uint) uint {
- if mode&ParseComments != 0 {
- return scanner.ScanComments
- }
- return 0
-}
-
-
-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)
- p.next()
-}
-
-
-// ----------------------------------------------------------------------------
-// Parsing support
-
-func (p *parser) printTrace(a ...interface{}) {
- const dots = ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " +
- ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "
- const n = uint(len(dots))
- fmt.Printf("%5d:%3d: ", p.pos.Line, p.pos.Column)
- i := 2 * p.indent
- for ; i > n; i -= n {
- fmt.Print(dots)
- }
- fmt.Print(dots[0:i])
- fmt.Println(a)
-}
-
-
-func trace(p *parser, msg string) *parser {
- p.printTrace(msg, "(")
- p.indent++
- return p
-}
-
-
-// Usage pattern: defer un(trace(p, "..."));
-func un(p *parser) {
- p.indent--
- p.printTrace(")")
-}
-
-
-// Advance to the next token.
-func (p *parser) next0() {
- // Because of one-token look-ahead, print the previous token
- // when tracing as it provides a more readable output. The
- // very first token (p.pos.Line == 0) is not initialized (it
- // is token.ILLEGAL), so don't print it .
- if p.trace && p.pos.Line > 0 {
- s := p.tok.String()
- switch {
- case p.tok.IsLiteral():
- p.printTrace(s, string(p.lit))
- case p.tok.IsOperator(), p.tok.IsKeyword():
- p.printTrace("\"" + s + "\"")
- default:
- p.printTrace(s)
- }
- }
-
- p.pos, p.tok, p.lit = p.scanner.Scan()
- p.optSemi = false
-}
-
-
-// Consume a comment and return it and the line on which it ends.
-func (p *parser) consumeComment() (comment *ast.Comment, endline int) {
- // /*-style comments may end on a different line than where they start.
- // Scan the comment for '\n' chars and adjust endline accordingly.
- endline = p.pos.Line
- if p.lit[1] == '*' {
- for _, b := range p.lit {
- if b == '\n' {
- endline++
- }
- }
- }
-
- comment = &ast.Comment{p.pos, p.lit}
- p.next0()
-
- return
-}
-
-
-// Consume a group of adjacent comments, add it to the parser's
-// comments list, and return the line of which the last comment
-// in the group ends. An empty line or non-comment token terminates
-// a comment group.
-//
-func (p *parser) consumeCommentGroup() int {
- list := new(vector.Vector)
- endline := p.pos.Line
- for p.tok == token.COMMENT && endline+1 >= p.pos.Line {
- var comment *ast.Comment
- comment, endline = p.consumeComment()
- list.Push(comment)
- }
-
- // convert list
- group := make([]*ast.Comment, list.Len())
- for i := 0; i < list.Len(); i++ {
- group[i] = list.At(i).(*ast.Comment)
- }
-
- // add comment group to the comments list
- g := &ast.CommentGroup{group, nil}
- if p.lastComment != nil {
- p.lastComment.Next = g
- } else {
- p.comments = g
- }
- p.lastComment = g
-
- return endline
-}
-
-
-// Advance to the next non-comment token. In the process, collect
-// any comment groups encountered, and remember the last lead and
-// and line comments.
-//
-// A lead comment is a comment group that starts and ends in a
-// line without any other tokens and that is followed by a non-comment
-// token on the line immediately after the comment group.
-//
-// A line comment is a comment group that follows a non-comment
-// token on the same line, and that has no tokens after it on the line
-// where it ends.
-//
-// Lead and line comments may be considered documentation that is
-// stored in the AST.
-//
-func (p *parser) next() {
- p.leadComment = nil
- p.lineComment = nil
- line := p.pos.Line // current line
- p.next0()
-
- if p.tok == token.COMMENT {
- if p.pos.Line == line {
- // The comment is on same line as previous token; it
- // cannot be a lead comment but may be a line comment.
- endline := p.consumeCommentGroup()
- if p.pos.Line != endline {
- // The next token is on a different line, thus
- // the last comment group is a line comment.
- p.lineComment = p.lastComment
- }
- }
-
- // consume successor comments, if any
- endline := -1
- for p.tok == token.COMMENT {
- endline = p.consumeCommentGroup()
- }
-
- if endline >= 0 && endline+1 == p.pos.Line {
- // The next token is following on the line immediately after the
- // comment group, thus the last comment group is a lead comment.
- p.leadComment = p.lastComment
- }
- }
-}
-
-
-func (p *parser) errorExpected(pos token.Position, msg string) {
- msg = "expected " + msg
- if pos.Offset == p.pos.Offset {
- // the error happened at the current position;
- // make the error message more specific
- msg += ", found '" + p.tok.String() + "'"
- if p.tok.IsLiteral() {
- msg += " " + string(p.lit)
- }
- }
- p.Error(pos, msg)
-}
-
-
-func (p *parser) expect(tok token.Token) token.Position {
- pos := p.pos
- if p.tok != tok {
- p.errorExpected(pos, "'"+tok.String()+"'")
- }
- p.next() // make progress in any case
- return pos
-}
-
-
-// ----------------------------------------------------------------------------
-// Common productions
-
-func (p *parser) parseIdent() *ast.Ident {
- obj := ast.NewObj(ast.Err, p.pos, "")
- if p.tok == token.IDENT {
- obj.Name = string(p.lit)
- p.next()
- } else {
- p.expect(token.IDENT) // use expect() error handling
- }
- return &ast.Ident{obj.Pos, obj}
-}
-
-
-func (p *parser) parseIdentList() []*ast.Ident {
- if p.trace {
- defer un(trace(p, "IdentList"))
- }
-
- list := new(vector.Vector)
- list.Push(p.parseIdent())
- for p.tok == token.COMMA {
- p.next()
- list.Push(p.parseIdent())
- }
-
- // convert vector
- idents := make([]*ast.Ident, list.Len())
- for i := 0; i < list.Len(); i++ {
- idents[i] = list.At(i).(*ast.Ident)
- }
-
- return idents
-}
-
-
-func (p *parser) parseExprList() []ast.Expr {
- if p.trace {
- defer un(trace(p, "ExpressionList"))
- }
-
- list := new(vector.Vector)
- list.Push(p.parseExpr())
- for p.tok == token.COMMA {
- p.next()
- list.Push(p.parseExpr())
- }
-
- // convert list
- exprs := make([]ast.Expr, list.Len())
- for i := 0; i < list.Len(); i++ {
- exprs[i] = list.At(i).(ast.Expr)
- }
-
- return exprs
-}
-
-
-// ----------------------------------------------------------------------------
-// Types
-
-func (p *parser) parseType() ast.Expr {
- if p.trace {
- defer un(trace(p, "Type"))
- }
-
- typ := p.tryType()
-
- if typ == nil {
- p.errorExpected(p.pos, "type")
- p.next() // make progress
- return &ast.BadExpr{p.pos}
- }
-
- return typ
-}
-
-
-func (p *parser) parseQualifiedIdent() ast.Expr {
- if p.trace {
- defer un(trace(p, "QualifiedIdent"))
- }
-
- var x ast.Expr = p.parseIdent()
- if p.tok == token.PERIOD {
- // first identifier is a package identifier
- p.next()
- sel := p.parseIdent()
- x = &ast.SelectorExpr{x, sel}
- }
- return x
-}
-
-
-func (p *parser) parseTypeName() ast.Expr {
- if p.trace {
- defer un(trace(p, "TypeName"))
- }
-
- return p.parseQualifiedIdent()
-}
-
-
-func (p *parser) parseArrayType(ellipsisOk bool) ast.Expr {
- if p.trace {
- defer un(trace(p, "ArrayType"))
- }
-
- lbrack := p.expect(token.LBRACK)
- var len ast.Expr
- if ellipsisOk && p.tok == token.ELLIPSIS {
- len = &ast.Ellipsis{p.pos, nil}
- p.next()
- } else if p.tok != token.RBRACK {
- len = p.parseExpr()
- }
- p.expect(token.RBRACK)
- elt := p.parseType()
-
- return &ast.ArrayType{lbrack, len, elt}
-}
-
-
-func (p *parser) makeIdentList(list *vector.Vector) []*ast.Ident {
- idents := make([]*ast.Ident, list.Len())
- for i := 0; i < list.Len(); i++ {
- ident, isIdent := list.At(i).(*ast.Ident)
- if !isIdent {
- pos := list.At(i).(ast.Expr).Pos()
- p.errorExpected(pos, "identifier")
- idents[i] = &ast.Ident{pos, ast.NewObj(ast.Err, pos, "")}
- }
- idents[i] = ident
- }
- return idents
-}
-
-
-func (p *parser) parseFieldDecl() *ast.Field {
- if p.trace {
- defer un(trace(p, "FieldDecl"))
- }
-
- doc := p.leadComment
-
- // a list of identifiers looks like a list of type names
- list := new(vector.Vector)
- for {
- // TODO(gri): do not allow ()'s here
- list.Push(p.parseType())
- if p.tok == token.COMMA {
- p.next()
- } else {
- break
- }
- }
-
- // if we had a list of identifiers, it must be followed by a type
- typ := p.tryType()
-
- // optional tag
- var tag []*ast.BasicLit
- if p.tok == token.STRING {
- tag = p.parseStringList(nil)
- }
-
- // analyze case
- var idents []*ast.Ident
- if typ != nil {
- // IdentifierList Type
- idents = p.makeIdentList(list)
- } else {
- // Type (anonymous field)
- if list.Len() == 1 {
- // TODO(gri): check that this looks like a type
- typ = list.At(0).(ast.Expr)
- } else {
- p.errorExpected(p.pos, "anonymous field")
- typ = &ast.BadExpr{p.pos}
- }
- }
-
- return &ast.Field{doc, idents, typ, tag, nil}
-}
-
-
-func (p *parser) parseStructType() *ast.StructType {
- if p.trace {
- defer un(trace(p, "StructType"))
- }
-
- pos := p.expect(token.STRUCT)
- lbrace := p.expect(token.LBRACE)
- list := new(vector.Vector)
- for p.tok == token.IDENT || p.tok == token.MUL {
- f := p.parseFieldDecl()
- if p.tok != token.RBRACE {
- p.expect(token.SEMICOLON)
- }
- f.Comment = p.lineComment
- list.Push(f)
- }
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
-
- // convert vector
- fields := make([]*ast.Field, list.Len())
- for i := list.Len() - 1; i >= 0; i-- {
- fields[i] = list.At(i).(*ast.Field)
- }
-
- return &ast.StructType{pos, lbrace, fields, rbrace, false}
-}
-
-
-func (p *parser) parsePointerType() *ast.StarExpr {
- if p.trace {
- defer un(trace(p, "PointerType"))
- }
-
- star := p.expect(token.MUL)
- base := p.parseType()
-
- return &ast.StarExpr{star, base}
-}
-
-
-func (p *parser) tryParameterType(ellipsisOk bool) ast.Expr {
- if ellipsisOk && p.tok == token.ELLIPSIS {
- pos := p.pos
- p.next()
- typ := p.tryType()
- if p.tok != token.RPAREN {
- p.Error(pos, "can use '...' for last parameter only")
- }
- return &ast.Ellipsis{pos, typ}
- }
- return p.tryType()
-}
-
-
-func (p *parser) parseParameterType(ellipsisOk bool) ast.Expr {
- typ := p.tryParameterType(ellipsisOk)
- if typ == nil {
- p.errorExpected(p.pos, "type")
- p.next() // make progress
- typ = &ast.BadExpr{p.pos}
- }
- return typ
-}
-
-
-func (p *parser) parseParameterDecl(ellipsisOk bool) (*vector.Vector, ast.Expr) {
- if p.trace {
- defer un(trace(p, "ParameterDecl"))
- }
-
- // a list of identifiers looks like a list of type names
- list := new(vector.Vector)
- for {
- // TODO(gri): do not allow ()'s here
- list.Push(p.parseParameterType(ellipsisOk))
- if p.tok == token.COMMA {
- p.next()
- } else {
- break
- }
- }
-
- // if we had a list of identifiers, it must be followed by a type
- typ := p.tryParameterType(ellipsisOk)
-
- return list, typ
-}
-
-
-func (p *parser) parseParameterList(ellipsisOk bool) []*ast.Field {
- if p.trace {
- defer un(trace(p, "ParameterList"))
- }
-
- list, typ := p.parseParameterDecl(ellipsisOk)
- if typ != nil {
- // IdentifierList Type
- idents := p.makeIdentList(list)
- list.Resize(0, 0)
- list.Push(&ast.Field{nil, idents, typ, nil, nil})
-
- for p.tok == token.COMMA {
- p.next()
- idents := p.parseIdentList()
- typ := p.parseParameterType(ellipsisOk)
- list.Push(&ast.Field{nil, idents, typ, nil, nil})
- }
-
- } else {
- // Type { "," Type } (anonymous parameters)
- // convert list of types into list of *Param
- for i := 0; i < list.Len(); i++ {
- list.Set(i, &ast.Field{Type: list.At(i).(ast.Expr)})
- }
- }
-
- // convert list
- params := make([]*ast.Field, list.Len())
- for i := 0; i < list.Len(); i++ {
- params[i] = list.At(i).(*ast.Field)
- }
-
- return params
-}
-
-
-func (p *parser) parseParameters(ellipsisOk bool) []*ast.Field {
- if p.trace {
- defer un(trace(p, "Parameters"))
- }
-
- var params []*ast.Field
- p.expect(token.LPAREN)
- if p.tok != token.RPAREN {
- params = p.parseParameterList(ellipsisOk)
- }
- p.expect(token.RPAREN)
-
- return params
-}
-
-
-func (p *parser) parseResult() []*ast.Field {
- if p.trace {
- defer un(trace(p, "Result"))
- }
-
- var results []*ast.Field
- if p.tok == token.LPAREN {
- results = p.parseParameters(false)
- } else if p.tok != token.FUNC {
- typ := p.tryType()
- if typ != nil {
- results = make([]*ast.Field, 1)
- results[0] = &ast.Field{Type: typ}
- }
- }
-
- return results
-}
-
-
-func (p *parser) parseSignature() (params []*ast.Field, results []*ast.Field) {
- if p.trace {
- defer un(trace(p, "Signature"))
- }
-
- params = p.parseParameters(true)
- results = p.parseResult()
-
- return
-}
-
-
-func (p *parser) parseFuncType() *ast.FuncType {
- if p.trace {
- defer un(trace(p, "FuncType"))
- }
-
- pos := p.expect(token.FUNC)
- params, results := p.parseSignature()
-
- return &ast.FuncType{pos, params, results}
-}
-
-
-func (p *parser) parseMethodSpec() *ast.Field {
- if p.trace {
- defer un(trace(p, "MethodSpec"))
- }
-
- doc := p.leadComment
- var idents []*ast.Ident
- var typ ast.Expr
- x := p.parseQualifiedIdent()
- if ident, isIdent := x.(*ast.Ident); isIdent && p.tok == token.LPAREN {
- // method
- idents = []*ast.Ident{ident}
- params, results := p.parseSignature()
- typ = &ast.FuncType{noPos, params, results}
- } else {
- // embedded interface
- typ = x
- }
-
- return &ast.Field{doc, idents, typ, nil, nil}
-}
-
-
-func (p *parser) parseInterfaceType() *ast.InterfaceType {
- if p.trace {
- defer un(trace(p, "InterfaceType"))
- }
-
- pos := p.expect(token.INTERFACE)
- lbrace := p.expect(token.LBRACE)
- list := new(vector.Vector)
- for p.tok == token.IDENT {
- m := p.parseMethodSpec()
- if p.tok != token.RBRACE {
- p.expect(token.SEMICOLON)
- }
- m.Comment = p.lineComment
- list.Push(m)
- }
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
-
- // convert vector
- methods := make([]*ast.Field, list.Len())
- for i := list.Len() - 1; i >= 0; i-- {
- methods[i] = list.At(i).(*ast.Field)
- }
-
- return &ast.InterfaceType{pos, lbrace, methods, rbrace, false}
-}
-
-
-func (p *parser) parseMapType() *ast.MapType {
- if p.trace {
- defer un(trace(p, "MapType"))
- }
-
- pos := p.expect(token.MAP)
- p.expect(token.LBRACK)
- key := p.parseType()
- p.expect(token.RBRACK)
- value := p.parseType()
-
- return &ast.MapType{pos, key, value}
-}
-
-
-func (p *parser) parseChanType() *ast.ChanType {
- if p.trace {
- defer un(trace(p, "ChanType"))
- }
-
- pos := p.pos
- dir := ast.SEND | ast.RECV
- if p.tok == token.CHAN {
- p.next()
- if p.tok == token.ARROW {
- p.next()
- dir = ast.SEND
- }
- } else {
- p.expect(token.ARROW)
- p.expect(token.CHAN)
- dir = ast.RECV
- }
- value := p.parseType()
-
- return &ast.ChanType{pos, dir, value}
-}
-
-
-func (p *parser) tryRawType(ellipsisOk bool) ast.Expr {
- switch p.tok {
- case token.IDENT:
- return p.parseTypeName()
- case token.LBRACK:
- return p.parseArrayType(ellipsisOk)
- case token.STRUCT:
- return p.parseStructType()
- case token.MUL:
- return p.parsePointerType()
- case token.FUNC:
- return p.parseFuncType()
- case token.INTERFACE:
- return p.parseInterfaceType()
- case token.MAP:
- return p.parseMapType()
- case token.CHAN, token.ARROW:
- return p.parseChanType()
- case token.LPAREN:
- lparen := p.pos
- p.next()
- typ := p.parseType()
- rparen := p.expect(token.RPAREN)
- return &ast.ParenExpr{lparen, typ, rparen}
- }
-
- // no type found
- return nil
-}
-
-
-func (p *parser) tryType() ast.Expr { return p.tryRawType(false) }
-
-
-// ----------------------------------------------------------------------------
-// Blocks
-
-func makeStmtList(list *vector.Vector) []ast.Stmt {
- stats := make([]ast.Stmt, list.Len())
- for i := 0; i < list.Len(); i++ {
- stats[i] = list.At(i).(ast.Stmt)
- }
- return stats
-}
-
-
-func (p *parser) parseStmtList() []ast.Stmt {
- if p.trace {
- defer un(trace(p, "StatementList"))
- }
-
- list := new(vector.Vector)
- expectSemi := false
- for p.tok != token.CASE && p.tok != token.DEFAULT && p.tok != token.RBRACE && p.tok != token.EOF {
- if expectSemi {
- p.expect(token.SEMICOLON)
- expectSemi = false
- }
- list.Push(p.parseStmt())
- if p.tok == token.SEMICOLON {
- p.next()
- } else if p.optSemi {
- p.optSemi = false // "consume" optional semicolon
- } else {
- expectSemi = true
- }
- }
-
- return makeStmtList(list)
-}
-
-
-func (p *parser) parseBlockStmt(idents []*ast.Ident) *ast.BlockStmt {
- if p.trace {
- defer un(trace(p, "BlockStmt"))
- }
-
- lbrace := p.expect(token.LBRACE)
- list := p.parseStmtList()
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
-
- return &ast.BlockStmt{lbrace, list, rbrace}
-}
-
-
-// ----------------------------------------------------------------------------
-// Expressions
-
-func (p *parser) parseStringList(x *ast.BasicLit) []*ast.BasicLit {
- if p.trace {
- defer un(trace(p, "StringList"))
- }
-
- list := new(vector.Vector)
- if x != nil {
- list.Push(x)
- }
-
- for p.tok == token.STRING {
- list.Push(&ast.BasicLit{p.pos, token.STRING, p.lit})
- p.next()
- }
-
- // convert list
- strings := make([]*ast.BasicLit, list.Len())
- for i := 0; i < list.Len(); i++ {
- strings[i] = list.At(i).(*ast.BasicLit)
- }
-
- return strings
-}
-
-
-func (p *parser) parseFuncTypeOrLit() ast.Expr {
- if p.trace {
- defer un(trace(p, "FuncTypeOrLit"))
- }
-
- typ := p.parseFuncType()
- if p.tok != token.LBRACE {
- // function type only
- return typ
- }
-
- p.exprLev++
- body := p.parseBlockStmt(nil)
- p.optSemi = false // function body requires separating ";"
- p.exprLev--
-
- return &ast.FuncLit{typ, body}
-}
-
-
-// parseOperand may return an expression or a raw type (incl. array
-// types of the form [...]T. Callers must verify the result.
-//
-func (p *parser) parseOperand() ast.Expr {
- if p.trace {
- defer un(trace(p, "Operand"))
- }
-
- switch p.tok {
- case token.IDENT:
- return p.parseIdent()
-
- case token.INT, token.FLOAT, token.CHAR, token.STRING:
- x := &ast.BasicLit{p.pos, p.tok, p.lit}
- p.next()
- if p.tok == token.STRING && p.tok == token.STRING {
- return &ast.StringList{p.parseStringList(x)}
- }
- return x
-
- case token.LPAREN:
- lparen := p.pos
- p.next()
- p.exprLev++
- x := p.parseExpr()
- p.exprLev--
- rparen := p.expect(token.RPAREN)
- return &ast.ParenExpr{lparen, x, rparen}
-
- case token.FUNC:
- return p.parseFuncTypeOrLit()
-
- default:
- t := p.tryRawType(true) // could be type for composite literal or conversion
- if t != nil {
- return t
- }
- }
-
- p.errorExpected(p.pos, "operand")
- p.next() // make progress
- return &ast.BadExpr{p.pos}
-}
-
-
-func (p *parser) parseSelectorOrTypeAssertion(x ast.Expr) ast.Expr {
- if p.trace {
- defer un(trace(p, "SelectorOrTypeAssertion"))
- }
-
- p.expect(token.PERIOD)
- if p.tok == token.IDENT {
- // selector
- sel := p.parseIdent()
- return &ast.SelectorExpr{x, sel}
- }
-
- // type assertion
- p.expect(token.LPAREN)
- var typ ast.Expr
- if p.tok == token.TYPE {
- // type switch: typ == nil
- p.next()
- } else {
- typ = p.parseType()
- }
- p.expect(token.RPAREN)
-
- return &ast.TypeAssertExpr{x, typ}
-}
-
-
-func (p *parser) parseIndexOrSlice(x ast.Expr) ast.Expr {
- if p.trace {
- defer un(trace(p, "IndexOrSlice"))
- }
-
- p.expect(token.LBRACK)
- p.exprLev++
- index := p.parseExpr()
- if p.tok == token.COLON {
- p.next()
- var end ast.Expr
- if p.tok != token.RBRACK {
- end = p.parseExpr()
- }
- x = &ast.SliceExpr{x, index, end}
- } else {
- x = &ast.IndexExpr{x, index}
- }
- p.exprLev--
- p.expect(token.RBRACK)
-
- return x
-}
-
-
-func (p *parser) parseCallOrConversion(fun ast.Expr) *ast.CallExpr {
- if p.trace {
- defer un(trace(p, "CallOrConversion"))
- }
-
- lparen := p.expect(token.LPAREN)
- p.exprLev++
- var args []ast.Expr
- if p.tok != token.RPAREN {
- args = p.parseExprList()
- }
- p.exprLev--
- rparen := p.expect(token.RPAREN)
-
- return &ast.CallExpr{fun, lparen, args, rparen}
-}
-
-
-func (p *parser) parseElement() ast.Expr {
- if p.trace {
- defer un(trace(p, "Element"))
- }
-
- x := p.parseExpr()
- if p.tok == token.COLON {
- colon := p.pos
- p.next()
- x = &ast.KeyValueExpr{x, colon, p.parseExpr()}
- }
-
- return x
-}
-
-
-func (p *parser) parseElementList() []ast.Expr {
- if p.trace {
- defer un(trace(p, "ElementList"))
- }
-
- list := new(vector.Vector)
- for p.tok != token.RBRACE && p.tok != token.EOF {
- list.Push(p.parseElement())
- if p.tok == token.COMMA {
- p.next()
- } else {
- break
- }
- }
-
- // convert list
- elts := make([]ast.Expr, list.Len())
- for i := 0; i < list.Len(); i++ {
- elts[i] = list.At(i).(ast.Expr)
- }
-
- return elts
-}
-
-
-func (p *parser) parseCompositeLit(typ ast.Expr) ast.Expr {
- if p.trace {
- defer un(trace(p, "CompositeLit"))
- }
-
- lbrace := p.expect(token.LBRACE)
- var elts []ast.Expr
- if p.tok != token.RBRACE {
- elts = p.parseElementList()
- }
- rbrace := p.expect(token.RBRACE)
- return &ast.CompositeLit{typ, lbrace, elts, rbrace}
-}
-
-
-// TODO(gri): Consider different approach to checking syntax after parsing:
-// Provide a arguments (set of flags) to parsing functions
-// restricting what they are supposed to accept depending
-// on context.
-
-// checkExpr checks that x is an expression (and not a type).
-func (p *parser) checkExpr(x ast.Expr) ast.Expr {
- // TODO(gri): should provide predicate in AST nodes
- switch t := x.(type) {
- case *ast.BadExpr:
- case *ast.Ident:
- case *ast.BasicLit:
- case *ast.StringList:
- case *ast.FuncLit:
- case *ast.CompositeLit:
- case *ast.ParenExpr:
- case *ast.SelectorExpr:
- case *ast.IndexExpr:
- case *ast.SliceExpr:
- case *ast.TypeAssertExpr:
- if t.Type == nil {
- // the form X.(type) is only allowed in type switch expressions
- p.errorExpected(x.Pos(), "expression")
- x = &ast.BadExpr{x.Pos()}
- }
- case *ast.CallExpr:
- case *ast.StarExpr:
- case *ast.UnaryExpr:
- if t.Op == token.RANGE {
- // the range operator is only allowed at the top of a for statement
- p.errorExpected(x.Pos(), "expression")
- x = &ast.BadExpr{x.Pos()}
- }
- case *ast.BinaryExpr:
- default:
- // all other nodes are not proper expressions
- p.errorExpected(x.Pos(), "expression")
- x = &ast.BadExpr{x.Pos()}
- }
- return x
-}
-
-
-// isTypeName returns true iff x is type name.
-func isTypeName(x ast.Expr) bool {
- // TODO(gri): should provide predicate in AST nodes
- switch t := x.(type) {
- case *ast.BadExpr:
- case *ast.Ident:
- case *ast.ParenExpr:
- return isTypeName(t.X) // TODO(gri): should (TypeName) be illegal?
- case *ast.SelectorExpr:
- return isTypeName(t.X)
- default:
- return false // all other nodes are not type names
- }
- return true
-}
-
-
-// isCompositeLitType returns true iff x is a legal composite literal type.
-func isCompositeLitType(x ast.Expr) bool {
- // TODO(gri): should provide predicate in AST nodes
- switch t := x.(type) {
- case *ast.BadExpr:
- case *ast.Ident:
- case *ast.ParenExpr:
- return isCompositeLitType(t.X)
- case *ast.SelectorExpr:
- return isTypeName(t.X)
- case *ast.ArrayType:
- case *ast.StructType:
- case *ast.MapType:
- default:
- return false // all other nodes are not legal composite literal types
- }
- return true
-}
-
-
-// checkExprOrType checks that x is an expression or a type
-// (and not a raw type such as [...]T).
-//
-func (p *parser) checkExprOrType(x ast.Expr) ast.Expr {
- // TODO(gri): should provide predicate in AST nodes
- switch t := x.(type) {
- case *ast.UnaryExpr:
- if t.Op == token.RANGE {
- // the range operator is only allowed at the top of a for statement
- p.errorExpected(x.Pos(), "expression")
- x = &ast.BadExpr{x.Pos()}
- }
- case *ast.ArrayType:
- if len, isEllipsis := t.Len.(*ast.Ellipsis); isEllipsis {
- p.Error(len.Pos(), "expected array length, found '...'")
- x = &ast.BadExpr{x.Pos()}
- }
- }
-
- // all other nodes are expressions or types
- return x
-}
-
-
-func (p *parser) parsePrimaryExpr() ast.Expr {
- if p.trace {
- defer un(trace(p, "PrimaryExpr"))
- }
-
- x := p.parseOperand()
-L: for {
- switch p.tok {
- case token.PERIOD:
- x = p.parseSelectorOrTypeAssertion(p.checkExpr(x))
- case token.LBRACK:
- x = p.parseIndexOrSlice(p.checkExpr(x))
- case token.LPAREN:
- x = p.parseCallOrConversion(p.checkExprOrType(x))
- case token.LBRACE:
- if isCompositeLitType(x) && (p.exprLev >= 0 || !isTypeName(x)) {
- x = p.parseCompositeLit(x)
- } else {
- break L
- }
- default:
- break L
- }
- }
-
- return x
-}
-
-
-func (p *parser) parseUnaryExpr() ast.Expr {
- if p.trace {
- defer un(trace(p, "UnaryExpr"))
- }
-
- switch p.tok {
- case token.ADD, token.SUB, token.NOT, token.XOR, token.ARROW, token.AND, token.RANGE:
- pos, op := p.pos, p.tok
- p.next()
- x := p.parseUnaryExpr()
- return &ast.UnaryExpr{pos, op, p.checkExpr(x)}
-
- case token.MUL:
- // unary "*" expression or pointer type
- pos := p.pos
- p.next()
- x := p.parseUnaryExpr()
- return &ast.StarExpr{pos, p.checkExprOrType(x)}
- }
-
- return p.parsePrimaryExpr()
-}
-
-
-func (p *parser) parseBinaryExpr(prec1 int) ast.Expr {
- if p.trace {
- defer un(trace(p, "BinaryExpr"))
- }
-
- x := p.parseUnaryExpr()
- for prec := p.tok.Precedence(); prec >= prec1; prec-- {
- for p.tok.Precedence() == prec {
- pos, op := p.pos, p.tok
- p.next()
- y := p.parseBinaryExpr(prec + 1)
- x = &ast.BinaryExpr{p.checkExpr(x), pos, op, p.checkExpr(y)}
- }
- }
-
- return x
-}
-
-
-// TODO(gri): parseExpr may return a type or even a raw type ([..]int) -
-// should reject when a type/raw type is obviously not allowed
-func (p *parser) parseExpr() ast.Expr {
- if p.trace {
- defer un(trace(p, "Expression"))
- }
-
- return p.parseBinaryExpr(token.LowestPrec + 1)
-}
-
-
-// ----------------------------------------------------------------------------
-// Statements
-
-
-func (p *parser) parseSimpleStmt(labelOk bool) ast.Stmt {
- if p.trace {
- defer un(trace(p, "SimpleStmt"))
- }
-
- x := p.parseExprList()
-
- switch p.tok {
- case token.COLON:
- // labeled statement
- p.next()
- if labelOk && len(x) == 1 {
- if label, isIdent := x[0].(*ast.Ident); isIdent {
- return &ast.LabeledStmt{label, p.parseStmt()}
- }
- }
- p.Error(x[0].Pos(), "illegal label declaration")
- return &ast.BadStmt{x[0].Pos()}
-
- case
- token.DEFINE, token.ASSIGN, token.ADD_ASSIGN,
- token.SUB_ASSIGN, token.MUL_ASSIGN, token.QUO_ASSIGN,
- token.REM_ASSIGN, token.AND_ASSIGN, token.OR_ASSIGN,
- token.XOR_ASSIGN, token.SHL_ASSIGN, token.SHR_ASSIGN, token.AND_NOT_ASSIGN:
- // assignment statement
- pos, tok := p.pos, p.tok
- p.next()
- y := p.parseExprList()
- return &ast.AssignStmt{x, pos, tok, y}
- }
-
- if len(x) > 1 {
- p.Error(x[0].Pos(), "only one expression allowed")
- // continue with first expression
- }
-
- if p.tok == token.INC || p.tok == token.DEC {
- // increment or decrement
- s := &ast.IncDecStmt{x[0], p.tok}
- p.next() // consume "++" or "--"
- return s
- }
-
- // expression
- return &ast.ExprStmt{x[0]}
-}
-
-
-func (p *parser) parseCallExpr() *ast.CallExpr {
- x := p.parseExpr()
- if call, isCall := x.(*ast.CallExpr); isCall {
- return call
- }
- p.errorExpected(x.Pos(), "function/method call")
- return nil
-}
-
-
-func (p *parser) parseGoStmt() ast.Stmt {
- if p.trace {
- defer un(trace(p, "GoStmt"))
- }
-
- pos := p.expect(token.GO)
- call := p.parseCallExpr()
- if call != nil {
- return &ast.GoStmt{pos, call}
- }
- return &ast.BadStmt{pos}
-}
-
-
-func (p *parser) parseDeferStmt() ast.Stmt {
- if p.trace {
- defer un(trace(p, "DeferStmt"))
- }
-
- pos := p.expect(token.DEFER)
- call := p.parseCallExpr()
- if call != nil {
- return &ast.DeferStmt{pos, call}
- }
- return &ast.BadStmt{pos}
-}
-
-
-func (p *parser) parseReturnStmt() *ast.ReturnStmt {
- if p.trace {
- defer un(trace(p, "ReturnStmt"))
- }
-
- pos := p.pos
- p.expect(token.RETURN)
- var x []ast.Expr
- if p.tok != token.SEMICOLON && p.tok != token.CASE && p.tok != token.DEFAULT && p.tok != token.RBRACE {
- x = p.parseExprList()
- }
-
- return &ast.ReturnStmt{pos, x}
-}
-
-
-func (p *parser) parseBranchStmt(tok token.Token) *ast.BranchStmt {
- if p.trace {
- defer un(trace(p, "BranchStmt"))
- }
-
- s := &ast.BranchStmt{p.pos, tok, nil}
- p.expect(tok)
- if tok != token.FALLTHROUGH && p.tok == token.IDENT {
- s.Label = p.parseIdent()
- }
-
- return s
-}
-
-
-func (p *parser) makeExpr(s ast.Stmt) ast.Expr {
- if s == nil {
- return nil
- }
- if es, isExpr := s.(*ast.ExprStmt); isExpr {
- return p.checkExpr(es.X)
- }
- p.Error(s.Pos(), "expected condition, found simple statement")
- return &ast.BadExpr{s.Pos()}
-}
-
-
-func (p *parser) parseControlClause(isForStmt bool) (s1, s2, s3 ast.Stmt) {
- if p.tok != token.LBRACE {
- prevLev := p.exprLev
- p.exprLev = -1
-
- if p.tok != token.SEMICOLON {
- s1 = p.parseSimpleStmt(false)
- }
- if p.tok == token.SEMICOLON {
- p.next()
- if p.tok != token.LBRACE && p.tok != token.SEMICOLON {
- s2 = p.parseSimpleStmt(false)
- }
- if isForStmt {
- // for statements have a 3rd section
- p.expect(token.SEMICOLON)
- if p.tok != token.LBRACE {
- s3 = p.parseSimpleStmt(false)
- }
- }
- } else {
- s1, s2 = nil, s1
- }
-
- p.exprLev = prevLev
- }
-
- return s1, s2, s3
-}
-
-
-func (p *parser) parseIfStmt() *ast.IfStmt {
- if p.trace {
- defer un(trace(p, "IfStmt"))
- }
-
- pos := p.expect(token.IF)
- s1, s2, _ := p.parseControlClause(false)
- body := p.parseBlockStmt(nil)
- var else_ ast.Stmt
- if p.tok == token.ELSE {
- p.next()
- else_ = p.parseStmt()
- }
-
- return &ast.IfStmt{pos, s1, p.makeExpr(s2), body, else_}
-}
-
-
-func (p *parser) parseCaseClause() *ast.CaseClause {
- if p.trace {
- defer un(trace(p, "CaseClause"))
- }
-
- // SwitchCase
- pos := p.pos
- var x []ast.Expr
- if p.tok == token.CASE {
- p.next()
- x = p.parseExprList()
- } else {
- p.expect(token.DEFAULT)
- }
-
- colon := p.expect(token.COLON)
- body := p.parseStmtList()
-
- return &ast.CaseClause{pos, x, colon, body}
-}
-
-
-func (p *parser) parseTypeList() []ast.Expr {
- if p.trace {
- defer un(trace(p, "TypeList"))
- }
-
- list := new(vector.Vector)
- list.Push(p.parseType())
- for p.tok == token.COMMA {
- p.next()
- list.Push(p.parseType())
- }
-
- // convert list
- exprs := make([]ast.Expr, list.Len())
- for i := 0; i < list.Len(); i++ {
- exprs[i] = list.At(i).(ast.Expr)
- }
-
- return exprs
-}
-
-
-func (p *parser) parseTypeCaseClause() *ast.TypeCaseClause {
- if p.trace {
- defer un(trace(p, "TypeCaseClause"))
- }
-
- // TypeSwitchCase
- pos := p.pos
- var types []ast.Expr
- if p.tok == token.CASE {
- p.next()
- types = p.parseTypeList()
- } else {
- p.expect(token.DEFAULT)
- }
-
- colon := p.expect(token.COLON)
- body := p.parseStmtList()
-
- return &ast.TypeCaseClause{pos, types, colon, body}
-}
-
-
-func isExprSwitch(s ast.Stmt) bool {
- if s == nil {
- return true
- }
- if e, ok := s.(*ast.ExprStmt); ok {
- if a, ok := e.X.(*ast.TypeAssertExpr); ok {
- return a.Type != nil // regular type assertion
- }
- return true
- }
- return false
-}
-
-
-func (p *parser) parseSwitchStmt() ast.Stmt {
- if p.trace {
- defer un(trace(p, "SwitchStmt"))
- }
-
- pos := p.expect(token.SWITCH)
- s1, s2, _ := p.parseControlClause(false)
-
- if isExprSwitch(s2) {
- lbrace := p.expect(token.LBRACE)
- cases := new(vector.Vector)
- for p.tok == token.CASE || p.tok == token.DEFAULT {
- cases.Push(p.parseCaseClause())
- }
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
- body := &ast.BlockStmt{lbrace, makeStmtList(cases), rbrace}
- return &ast.SwitchStmt{pos, s1, p.makeExpr(s2), body}
- }
-
- // type switch
- // TODO(gri): do all the checks!
- lbrace := p.expect(token.LBRACE)
- cases := new(vector.Vector)
- for p.tok == token.CASE || p.tok == token.DEFAULT {
- cases.Push(p.parseTypeCaseClause())
- }
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
- body := &ast.BlockStmt{lbrace, makeStmtList(cases), rbrace}
- return &ast.TypeSwitchStmt{pos, s1, s2, body}
-}
-
-
-func (p *parser) parseCommClause() *ast.CommClause {
- if p.trace {
- defer un(trace(p, "CommClause"))
- }
-
- // CommCase
- pos := p.pos
- var tok token.Token
- var lhs, rhs ast.Expr
- if p.tok == token.CASE {
- p.next()
- if p.tok == token.ARROW {
- // RecvExpr without assignment
- rhs = p.parseExpr()
- } else {
- // SendExpr or RecvExpr
- rhs = p.parseExpr()
- if p.tok == token.ASSIGN || p.tok == token.DEFINE {
- // RecvExpr with assignment
- tok = p.tok
- p.next()
- lhs = rhs
- if p.tok == token.ARROW {
- rhs = p.parseExpr()
- } else {
- p.expect(token.ARROW) // use expect() error handling
- }
- }
- // else SendExpr
- }
- } else {
- p.expect(token.DEFAULT)
- }
-
- colon := p.expect(token.COLON)
- body := p.parseStmtList()
-
- return &ast.CommClause{pos, tok, lhs, rhs, colon, body}
-}
-
-
-func (p *parser) parseSelectStmt() *ast.SelectStmt {
- if p.trace {
- defer un(trace(p, "SelectStmt"))
- }
-
- pos := p.expect(token.SELECT)
- lbrace := p.expect(token.LBRACE)
- cases := new(vector.Vector)
- for p.tok == token.CASE || p.tok == token.DEFAULT {
- cases.Push(p.parseCommClause())
- }
- rbrace := p.expect(token.RBRACE)
- p.optSemi = true
- body := &ast.BlockStmt{lbrace, makeStmtList(cases), rbrace}
-
- return &ast.SelectStmt{pos, body}
-}
-
-
-func (p *parser) parseForStmt() ast.Stmt {
- if p.trace {
- defer un(trace(p, "ForStmt"))
- }
-
- pos := p.expect(token.FOR)
- s1, s2, s3 := p.parseControlClause(true)
- body := p.parseBlockStmt(nil)
-
- if as, isAssign := s2.(*ast.AssignStmt); isAssign {
- // possibly a for statement with a range clause; check assignment operator
- if as.Tok != token.ASSIGN && as.Tok != token.DEFINE {
- p.errorExpected(as.TokPos, "'=' or ':='")
- return &ast.BadStmt{pos}
- }
- // check lhs
- var key, value ast.Expr
- switch len(as.Lhs) {
- case 2:
- value = as.Lhs[1]
- fallthrough
- case 1:
- key = as.Lhs[0]
- default:
- p.errorExpected(as.Lhs[0].Pos(), "1 or 2 expressions")
- return &ast.BadStmt{pos}
- }
- // check rhs
- if len(as.Rhs) != 1 {
- p.errorExpected(as.Rhs[0].Pos(), "1 expressions")
- return &ast.BadStmt{pos}
- }
- if rhs, isUnary := as.Rhs[0].(*ast.UnaryExpr); isUnary && rhs.Op == token.RANGE {
- // rhs is range expression; check lhs
- return &ast.RangeStmt{pos, key, value, as.TokPos, as.Tok, rhs.X, body}
- } else {
- p.errorExpected(s2.Pos(), "range clause")
- return &ast.BadStmt{pos}
- }
- } else {
- // regular for statement
- return &ast.ForStmt{pos, s1, p.makeExpr(s2), s3, body}
- }
-
- panic() // unreachable
- return nil
-}
-
-
-func (p *parser) parseStmt() ast.Stmt {
- if p.trace {
- defer un(trace(p, "Statement"))
- }
-
- switch p.tok {
- case token.CONST, token.TYPE, token.VAR:
- decl, _ := p.parseDecl(false) // do not consume trailing semicolon
- return &ast.DeclStmt{decl}
- case
- // tokens that may start a top-level expression
- token.IDENT, token.INT, token.FLOAT, token.CHAR, token.STRING, token.FUNC, token.LPAREN, // operand
- token.LBRACK, token.STRUCT, // composite type
- token.MUL, token.AND, token.ARROW, token.ADD, token.SUB, token.XOR: // unary operators
- return p.parseSimpleStmt(true)
- case token.GO:
- return p.parseGoStmt()
- case token.DEFER:
- return p.parseDeferStmt()
- case token.RETURN:
- return p.parseReturnStmt()
- case token.BREAK, token.CONTINUE, token.GOTO, token.FALLTHROUGH:
- return p.parseBranchStmt(p.tok)
- case token.LBRACE:
- return p.parseBlockStmt(nil)
- case token.IF:
- return p.parseIfStmt()
- case token.SWITCH:
- return p.parseSwitchStmt()
- case token.SELECT:
- return p.parseSelectStmt()
- case token.FOR:
- return p.parseForStmt()
- case token.SEMICOLON, token.RBRACE:
- // don't consume the ";", it is the separator following the empty statement
- return &ast.EmptyStmt{p.pos}
- }
-
- // no statement found
- p.errorExpected(p.pos, "statement")
- p.next() // make progress
- return &ast.BadStmt{p.pos}
-}
-
-
-// ----------------------------------------------------------------------------
-// Declarations
-
-type parseSpecFunction func(p *parser, doc *ast.CommentGroup, getSemi bool) (spec ast.Spec, gotSemi bool)
-
-
-// Consume semicolon if there is one and getSemi is set, and get any line comment.
-// Return the comment if any and indicate if a semicolon was consumed.
-//
-func (p *parser) parseComment(getSemi bool) (comment *ast.CommentGroup, gotSemi bool) {
- if getSemi && p.tok == token.SEMICOLON {
- p.next()
- gotSemi = true
- }
- return p.lineComment, gotSemi
-}
-
-
-func parseImportSpec(p *parser, doc *ast.CommentGroup, getSemi bool) (spec ast.Spec, gotSemi bool) {
- if p.trace {
- defer un(trace(p, "ImportSpec"))
- }
-
- var ident *ast.Ident
- if p.tok == token.PERIOD {
- ident = &ast.Ident{p.pos, ast.NewObj(ast.Err, p.pos, ".")}
- p.next()
- } else if p.tok == token.IDENT {
- ident = p.parseIdent()
- }
-
- var path []*ast.BasicLit
- if p.tok == token.STRING {
- path = p.parseStringList(nil)
- } else {
- p.expect(token.STRING) // use expect() error handling
- }
-
- comment, gotSemi := p.parseComment(getSemi)
-
- return &ast.ImportSpec{doc, ident, path, comment}, gotSemi
-}
-
-
-func parseConstSpec(p *parser, doc *ast.CommentGroup, getSemi bool) (spec ast.Spec, gotSemi bool) {
- if p.trace {
- defer un(trace(p, "ConstSpec"))
- }
-
- idents := p.parseIdentList()
- typ := p.tryType()
- var values []ast.Expr
- if typ != nil || p.tok == token.ASSIGN {
- p.expect(token.ASSIGN)
- values = p.parseExprList()
- }
- comment, gotSemi := p.parseComment(getSemi)
-
- return &ast.ValueSpec{doc, idents, typ, values, comment}, gotSemi
-}
-
-
-func parseTypeSpec(p *parser, doc *ast.CommentGroup, getSemi bool) (spec ast.Spec, gotSemi bool) {
- if p.trace {
- defer un(trace(p, "TypeSpec"))
- }
-
- ident := p.parseIdent()
- typ := p.parseType()
- comment, gotSemi := p.parseComment(getSemi)
-
- return &ast.TypeSpec{doc, ident, typ, comment}, gotSemi
-}
-
-
-func parseVarSpec(p *parser, doc *ast.CommentGroup, getSemi bool) (spec ast.Spec, gotSemi bool) {
- if p.trace {
- defer un(trace(p, "VarSpec"))
- }
-
- idents := p.parseIdentList()
- typ := p.tryType()
- var values []ast.Expr
- if typ == nil || p.tok == token.ASSIGN {
- p.expect(token.ASSIGN)
- values = p.parseExprList()
- }
- comment, gotSemi := p.parseComment(getSemi)
-
- return &ast.ValueSpec{doc, idents, typ, values, comment}, gotSemi
-}
-
-
-func (p *parser) parseGenDecl(keyword token.Token, f parseSpecFunction, getSemi bool) (decl *ast.GenDecl, gotSemi bool) {
- if p.trace {
- defer un(trace(p, keyword.String()+"Decl"))
- }
-
- doc := p.leadComment
- pos := p.expect(keyword)
- var lparen, rparen token.Position
- list := new(vector.Vector)
- if p.tok == token.LPAREN {
- lparen = p.pos
- p.next()
- for p.tok != token.RPAREN && p.tok != token.EOF {
- doc := p.leadComment
- spec, semi := f(p, doc, true) // consume semicolon if any
- list.Push(spec)
- if !semi {
- break
- }
- }
- rparen = p.expect(token.RPAREN)
-
- if getSemi && p.tok == token.SEMICOLON {
- p.next()
- gotSemi = true
- } else {
- p.optSemi = true
- }
- } else {
- spec, semi := f(p, nil, getSemi)
- list.Push(spec)
- gotSemi = semi
- }
-
- // convert vector
- specs := make([]ast.Spec, list.Len())
- for i := 0; i < list.Len(); i++ {
- specs[i] = list.At(i).(ast.Spec)
- }
-
- return &ast.GenDecl{doc, pos, keyword, lparen, specs, rparen}, gotSemi
-}
-
-
-func (p *parser) parseReceiver() *ast.Field {
- if p.trace {
- defer un(trace(p, "Receiver"))
- }
-
- pos := p.pos
- par := p.parseParameters(false)
-
- // must have exactly one receiver
- if len(par) != 1 || len(par) == 1 && len(par[0].Names) > 1 {
- p.errorExpected(pos, "exactly one receiver")
- return &ast.Field{Type: &ast.BadExpr{noPos}}
- }
-
- recv := par[0]
-
- // recv type must be TypeName or *TypeName
- base := recv.Type
- if ptr, isPtr := base.(*ast.StarExpr); isPtr {
- base = ptr.X
- }
- if !isTypeName(base) {
- p.errorExpected(base.Pos(), "type name")
- }
-
- return recv
-}
-
-
-func (p *parser) parseFunctionDecl() *ast.FuncDecl {
- if p.trace {
- defer un(trace(p, "FunctionDecl"))
- }
-
- doc := p.leadComment
- pos := p.expect(token.FUNC)
-
- var recv *ast.Field
- if p.tok == token.LPAREN {
- recv = p.parseReceiver()
- }
-
- ident := p.parseIdent()
- params, results := p.parseSignature()
-
- var body *ast.BlockStmt
- if p.tok == token.LBRACE {
- body = p.parseBlockStmt(nil)
- }
-
- return &ast.FuncDecl{doc, recv, ident, &ast.FuncType{pos, params, results}, body}
-}
-
-
-func (p *parser) parseDecl(getSemi bool) (decl ast.Decl, gotSemi bool) {
- if p.trace {
- defer un(trace(p, "Declaration"))
- }
-
- var f parseSpecFunction
- switch p.tok {
- case token.CONST:
- f = parseConstSpec
-
- case token.TYPE:
- f = parseTypeSpec
-
- case token.VAR:
- f = parseVarSpec
-
- case token.FUNC:
- decl = p.parseFunctionDecl()
- _, gotSemi := p.parseComment(getSemi)
- return decl, gotSemi
-
- default:
- pos := p.pos
- p.errorExpected(pos, "declaration")
- decl = &ast.BadDecl{pos}
- gotSemi = getSemi && p.tok == token.SEMICOLON
- p.next() // make progress in any case
- return decl, gotSemi
- }
-
- return p.parseGenDecl(p.tok, f, getSemi)
-}
-
-
-func (p *parser) parseDeclList() []ast.Decl {
- if p.trace {
- defer un(trace(p, "DeclList"))
- }
-
- list := new(vector.Vector)
- for p.tok != token.EOF {
- decl, _ := p.parseDecl(true) // consume optional semicolon
- list.Push(decl)
- }
-
- // convert vector
- decls := make([]ast.Decl, list.Len())
- for i := 0; i < list.Len(); i++ {
- decls[i] = list.At(i).(ast.Decl)
- }
-
- return decls
-}
-
-
-// ----------------------------------------------------------------------------
-// Source files
-
-func (p *parser) parseFile() *ast.File {
- if p.trace {
- defer un(trace(p, "File"))
- }
-
- // package clause
- doc := p.leadComment
- pos := p.expect(token.PACKAGE)
- ident := p.parseIdent()
-
- // Common error: semicolon after package clause.
- // Accept and report it for better error synchronization.
- if p.tok == token.SEMICOLON {
- p.Error(p.pos, "expected declaration, found ';'")
- p.next()
- }
-
- var decls []ast.Decl
-
- // Don't bother parsing the rest if we had errors already.
- // Likely not a Go source file at all.
-
- if p.ErrorCount() == 0 && p.mode&PackageClauseOnly == 0 {
- // import decls
- list := new(vector.Vector)
- for p.tok == token.IMPORT {
- decl, _ := p.parseGenDecl(token.IMPORT, parseImportSpec, true) // consume optional semicolon
- list.Push(decl)
- }
-
- if p.mode&ImportsOnly == 0 {
- // rest of package body
- for p.tok != token.EOF {
- decl, _ := p.parseDecl(true) // consume optional semicolon
- list.Push(decl)
- }
- }
-
- // convert declaration list
- decls = make([]ast.Decl, list.Len())
- for i := 0; i < list.Len(); i++ {
- decls[i] = list.At(i).(ast.Decl)
- }
- }
-
- return &ast.File{doc, pos, ident, decls, p.comments}
-}
diff --git a/src/pkg/exp/parser/parser_test.go b/src/pkg/exp/parser/parser_test.go
deleted file mode 100644
index 2aefaa1cff..0000000000
--- a/src/pkg/exp/parser/parser_test.go
+++ /dev/null
@@ -1,95 +0,0 @@
-// 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 oldParser
-
-import (
- "os"
- "testing"
-)
-
-
-var illegalInputs = []interface{}{
- nil,
- 3.14,
- []byte(nil),
- "foo!",
-}
-
-
-func TestParseIllegalInputs(t *testing.T) {
- for _, src := range illegalInputs {
- _, err := ParseFile("", src, 0)
- if err == nil {
- t.Errorf("ParseFile(%v) should have failed", src)
- }
- }
-}
-
-
-var validPrograms = []interface{}{
- `package main`,
- `package main import "fmt" func main() { fmt.Println("Hello, World!") }`,
- `package main func main() { if f(T{}) {} }`,
-}
-
-
-func TestParseValidPrograms(t *testing.T) {
- for _, src := range validPrograms {
- _, err := ParseFile("", src, 0)
- if err != nil {
- t.Errorf("ParseFile(%q): %v", src, err)
- }
- }
-}
-
-
-var validFiles = []string{
- "parser.go",
- "parser_test.go",
-}
-
-
-func TestParse3(t *testing.T) {
- return // disabled since the parser only accepts old syntax
- for _, filename := range validFiles {
- _, err := ParseFile(filename, nil, 0)
- if err != nil {
- t.Errorf("ParseFile(%s): %v", filename, err)
- }
- }
-}
-
-
-func nameFilter(filename string) bool {
- switch filename {
- case "parser.go":
- case "interface.go":
- case "parser_test.go":
- default:
- return false
- }
- return true
-}
-
-
-func dirFilter(d *os.Dir) bool { return nameFilter(d.Name) }
-
-
-func TestParse4(t *testing.T) {
- return // disabled since the parser only accepts old syntax
- path := "."
- pkg, err := ParsePackage(path, dirFilter, 0)
- if err != nil {
- t.Fatalf("ParsePackage(%s): %v", path, err)
- }
- if pkg.Name != "oldParser" {
- t.Errorf("incorrect package name: %s", pkg.Name)
- }
- for filename, _ := range pkg.Files {
- if !nameFilter(filename) {
- t.Errorf("unexpected package file: %s", filename)
- }
- }
-}
diff --git a/src/pkg/go/ast/ast.go b/src/pkg/go/ast/ast.go
index 95700cb14d..0976a5ec78 100644
--- a/src/pkg/go/ast/ast.go
+++ b/src/pkg/go/ast/ast.go
@@ -90,7 +90,7 @@ type Field struct {
Doc *CommentGroup // associated documentation; or nil
Names []*Ident // field/method/parameter names; or nil if anonymous field
Type Expr // field/method/parameter type
- Tag []*BasicLit // field tag; or nil
+ Tag *BasicLit // field tag; or nil
Comment *CommentGroup // line comments; or nil
}
@@ -136,17 +136,6 @@ type (
Value []byte // literal string; e.g. 42, 0x7f, 3.14, 1e-9, 'a', '\x7f', "foo" or `\m\n\o`
}
- // A StringList node represents a sequence of adjacent string literals.
- // A single string literal (common case) is represented by a BasicLit
- // node; StringList nodes are used only if there are two or more string
- // literals in a sequence.
- // TODO(gri) Deprecated. StringLists are only created by exp/parser;
- // Remove when exp/parser is removed.
- //
- StringList struct {
- Strings []*BasicLit // list of strings, len(Strings) > 1
- }
-
// A FuncLit node represents a function literal.
FuncLit struct {
Type *FuncType // function type
@@ -309,7 +298,6 @@ type (
// Pos() implementations for expression/type where the position
// corresponds to the position of a sub-node.
//
-func (x *StringList) Pos() token.Position { return x.Strings[0].Pos() }
func (x *FuncLit) Pos() token.Position { return x.Type.Pos() }
func (x *CompositeLit) Pos() token.Position { return x.Type.Pos() }
func (x *SelectorExpr) Pos() token.Position { return x.X.Pos() }
@@ -327,7 +315,6 @@ func (x *BadExpr) exprNode() {}
func (x *Ident) exprNode() {}
func (x *Ellipsis) exprNode() {}
func (x *BasicLit) exprNode() {}
-func (x *StringList) exprNode() {}
func (x *FuncLit) exprNode() {}
func (x *CompositeLit) exprNode() {}
func (x *ParenExpr) exprNode() {}
@@ -604,7 +591,7 @@ type (
ImportSpec struct {
Doc *CommentGroup // associated documentation; or nil
Name *Ident // local package name (including "."); or nil
- Path []*BasicLit // package path
+ Path *BasicLit // package path
Comment *CommentGroup // line comments; or nil
}
@@ -634,7 +621,7 @@ func (s *ImportSpec) Pos() token.Position {
if s.Name != nil {
return s.Name.Pos()
}
- return s.Path[0].Pos()
+ return s.Path.Pos()
}
func (s *ValueSpec) Pos() token.Position { return s.Names[0].Pos() }
diff --git a/src/pkg/go/ast/walk.go b/src/pkg/go/ast/walk.go
index 33a2d32940..ee2c89cbe1 100644
--- a/src/pkg/go/ast/walk.go
+++ b/src/pkg/go/ast/walk.go
@@ -74,20 +74,13 @@ func Walk(v Visitor, node interface{}) {
walkCommentGroup(v, n.Doc)
Walk(v, n.Names)
Walk(v, n.Type)
- for _, x := range n.Tag {
- Walk(v, x)
- }
+ Walk(v, n.Tag)
walkCommentGroup(v, n.Comment)
// Expressions
case *BadExpr, *Ident, *Ellipsis, *BasicLit:
// nothing to do
- case *StringList:
- for _, x := range n.Strings {
- Walk(v, x)
- }
-
case *FuncLit:
if n != nil {
Walk(v, n.Type)
@@ -249,9 +242,7 @@ func Walk(v Visitor, node interface{}) {
case *ImportSpec:
walkCommentGroup(v, n.Doc)
walkIdent(v, n.Name)
- for _, x := range n.Path {
- Walk(v, x)
- }
+ Walk(v, n.Path)
walkCommentGroup(v, n.Comment)
case *ValueSpec:
diff --git a/src/pkg/go/parser/parser.go b/src/pkg/go/parser/parser.go
index d848d2392b..15bb2d6125 100644
--- a/src/pkg/go/parser/parser.go
+++ b/src/pkg/go/parser/parser.go
@@ -526,11 +526,10 @@ func (p *parser) parseFieldDecl() *ast.Field {
typ := p.tryType()
// optional tag
- var tag []*ast.BasicLit
+ var tag *ast.BasicLit
if p.tok == token.STRING {
- x := &ast.BasicLit{p.pos, p.tok, p.lit}
+ tag = &ast.BasicLit{p.pos, p.tok, p.lit}
p.next()
- tag = []*ast.BasicLit{x}
}
// analyze case
@@ -1129,7 +1128,6 @@ func (p *parser) checkExpr(x ast.Expr) ast.Expr {
case *ast.BadExpr:
case *ast.Ident:
case *ast.BasicLit:
- case *ast.StringList:
case *ast.FuncLit:
case *ast.CompositeLit:
case *ast.ParenExpr:
@@ -1827,11 +1825,10 @@ func parseImportSpec(p *parser, doc *ast.CommentGroup) ast.Spec {
p.declIdent(p.fileScope, ident)
}
- var path []*ast.BasicLit
+ var path *ast.BasicLit
if p.tok == token.STRING {
- x := &ast.BasicLit{p.pos, p.tok, p.lit}
+ path = &ast.BasicLit{p.pos, p.tok, p.lit}
p.next()
- path = []*ast.BasicLit{x}
} else {
p.expect(token.STRING) // use expect() error handling
}
diff --git a/src/pkg/go/printer/nodes.go b/src/pkg/go/printer/nodes.go
index 218ad765d8..9a7519ba35 100644
--- a/src/pkg/go/printer/nodes.go
+++ b/src/pkg/go/printer/nodes.go
@@ -396,7 +396,7 @@ func (p *printer) fieldList(lbrace token.Position, list []*ast.Field, rbrace tok
p.print(sep)
}
p.print(sep)
- p.expr(&ast.StringList{f.Tag}, &ml)
+ p.expr(f.Tag, &ml)
extraTabs = 0
}
if f.Comment != nil {
@@ -680,9 +680,6 @@ func (p *printer) expr1(expr ast.Expr, prec1, depth int, ctxt exprContext, multi
case *ast.BasicLit:
p.print(x)
- case *ast.StringList:
- p.stringList(x.Strings, multiLine)
-
case *ast.FuncLit:
p.expr(x.Type, multiLine)
p.funcBody(x.Body, distance(x.Type.Pos(), p.pos), true, multiLine)
@@ -1117,9 +1114,9 @@ func (p *printer) spec(spec ast.Spec, n int, context declContext, multiLine *boo
if s.Name != nil {
p.expr(s.Name, multiLine)
p.print(blank)
- p.moveCommentsAfter(s.Path[0].Pos())
+ p.moveCommentsAfter(s.Path.Pos())
}
- p.expr(&ast.StringList{s.Path}, multiLine)
+ p.expr(s.Path, multiLine)
comment = s.Comment
case *ast.ValueSpec: