示例#1
0
func (p *gcParser) expect(tok int) string {
	lit := p.lit
	if p.tok != tok {
		p.errorf("expected %q, got %q (%q)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit)
	}
	p.next()
	return lit
}
示例#2
0
// Export        = "PackageClause { Decl } "$$" .
// PackageClause = "package" identifier [ "safe" ] "\n" .
//
func (p *gcParser) parseExport() *ast.Object {
	p.expectKeyword("package")
	name := p.expect(scanner.Ident)
	if p.tok != '\n' {
		// A package is safe if it was compiled with the -u flag,
		// which disables the unsafe package.
		// TODO(gri) remember "safe" package
		p.expectKeyword("safe")
	}
	p.expect('\n')

	assert(p.imports[p.id] == nil)
	pkg := ast.NewObj(ast.Pkg, name)
	pkg.Data = ast.NewScope(nil)
	p.imports[p.id] = pkg

	for p.tok != '$' && p.tok != scanner.EOF {
		p.parseDecl()
	}

	if ch := p.scanner.Peek(); p.tok != '$' || ch != '$' {
		// don't call next()/expect() since reading past the
		// export data may cause scanner errors (e.g. NUL chars)
		p.errorf("expected '$$', got %s %c", scanner.TokenString(p.tok), ch)
	}

	if n := p.scanner.ErrorCount; n != 0 {
		p.errorf("expected no scanner errors, got %d", n)
	}

	return pkg
}
示例#3
0
文件: parser.go 项目: aubonbeurre/gcc
func (p *parser) expect(tok rune) scanner.Position {
	pos := p.pos
	if p.tok != tok {
		p.errorExpected(pos, scanner.TokenString(tok))
	}
	p.next() // make progress in any case
	return pos
}
示例#4
0
func (p *gcParser) next() {
	p.tok = p.scanner.Scan()
	switch p.tok {
	case scanner.Ident, scanner.Int, scanner.String:
		p.lit = p.scanner.TokenText()
	default:
		p.lit = ""
	}
	if trace {
		fmt.Printf("%s: %q -> %q\n", scanner.TokenString(p.tok), p.scanner.TokenText(), p.lit)
	}
}
示例#5
0
文件: parser.go 项目: aubonbeurre/gcc
func (p *parser) errorExpected(pos scanner.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 " + scanner.TokenString(p.tok)
		if p.tok < 0 {
			msg += " " + p.lit
		}
	}
	p.error(pos, msg)
}
示例#6
0
// Type =
//	BasicType | TypeName | ArrayType | SliceType | StructType |
//      PointerType | FuncType | InterfaceType | MapType | ChanType |
//      "(" Type ")" .
// BasicType = ident .
// TypeName = ExportedName .
// SliceType = "[" "]" Type .
// PointerType = "*" Type .
// FuncType = "func" Signature .
//
func (p *gcParser) parseType() Type {
	switch p.tok {
	case scanner.Ident:
		switch p.lit {
		default:
			return p.parseBasicType()
		case "struct":
			return p.parseStructType()
		case "func":
			// FuncType
			p.next()
			return p.parseSignature()
		case "interface":
			return p.parseInterfaceType()
		case "map":
			return p.parseMapType()
		case "chan":
			return p.parseChanType()
		}
	case '@':
		// TypeName
		pkg, name := p.parseExportedName()
		return p.declare(pkg.Data.(*ast.Scope), ast.Typ, name).Type.(Type)
	case '[':
		p.next() // look ahead
		if p.tok == ']' {
			// SliceType
			p.next()
			return &Slice{Elt: p.parseType()}
		}
		return p.parseArrayType()
	case '*':
		// PointerType
		p.next()
		return &Pointer{Base: p.parseType()}
	case '<':
		return p.parseChanType()
	case '(':
		// "(" Type ")"
		p.next()
		typ := p.parseType()
		p.expect(')')
		return typ
	}
	p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit)
	return nil
}
示例#7
0
// Type =
//	BasicType | TypeName | ArrayType | SliceType | StructType |
//      PointerType | FuncType | InterfaceType | MapType | ChanType |
//      "(" Type ")" .
// BasicType = ident .
// TypeName = ExportedName .
// SliceType = "[" "]" Type .
// PointerType = "*" Type .
//
func (p *gcParser) parseType() Type {
	switch p.tok {
	case scanner.Ident:
		switch p.lit {
		default:
			return p.parseBasicType()
		case "struct":
			return p.parseStructType()
		case "func":
			p.next() // parseFuncType assumes "func" is already consumed
			return p.parseFuncType()
		case "interface":
			return p.parseInterfaceType()
		case "map":
			return p.parseMapType()
		case "chan":
			return p.parseChanType()
		}
	case scanner.String:
		// TypeName
		return p.parseExportedName(ast.Typ).Type.(Type)
	case '[':
		p.next() // look ahead
		if p.tok == ']' {
			// SliceType
			p.next()
			return &Slice{Elt: p.parseType()}
		}
		return p.parseArrayType()
	case '*':
		// PointerType
		p.next()
		return &Pointer{Base: p.parseType()}
	case '<':
		return p.parseChanType()
	case '(':
		// "(" Type ")"
		p.next()
		typ := p.parseType()
		p.expect(')')
		return typ
	}
	p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit)
	return nil
}
示例#8
0
// Type =
//	BasicType | TypeName | ArrayType | SliceType | StructType |
//      PointerType | FuncType | InterfaceType | MapType | ChanType |
//      "(" Type ")" .
// BasicType = ident .
// TypeName = ExportedName .
// SliceType = "[" "]" Type .
// PointerType = "*" Type .
// FuncType = "func" Signature .
func (p *gcParser) parseType() ast.Expr {
	switch p.tok {
	case scanner.Ident:
		switch p.lit {
		case "struct":
			return p.parseStrucType()
		case "func":
			p.next()
			return p.parseSignature()
		case "interface":
			return p.parseInterfaceType()
		case "map":
			return p.parseMapType()
		case "chan":
			return p.parseChanType()
		default:
			lit := p.lit
			p.next()
			return ast.NewIdent(lit)
		}
	case '@':
		return p.parseExportedName()
	case '[':
		return p.parseArrayOrSliceType()
	case '*':
		p.next()
		return &ast.StarExpr{X: p.parseType()}
	case '<':
		return p.parseChanType()
	case '(':
		p.next()
		typ := p.parseType()
		p.expect(')')
		return typ
	}
	p.errorf("unexpected token: %s", scanner.TokenString(p.tok))
	return nil
}
示例#9
0
文件: json.go 项目: saschpe/go-json
/*func (d *Decoder) decode(src io.Reader) {

}
*/
func main() {
	flag.Parse()
	if flag.NArg() != 1 {
		fmt.Println("wrong number of arguments")
		os.Exit(1)
	}

	file, err := os.Open(flag.Arg(0), os.O_RDONLY, 0)
	if file == nil {
		fmt.Printf("can't open file; err=%s\n", err.String())
		os.Exit(1)
	}

	var s scanner.Scanner
	s.Init(file)
	tok := s.Scan()
	for tok != scanner.EOF {
		fmt.Println(scanner.TokenString(tok))
		tok = s.Scan()
	}
	fmt.Println()

	file.Close()
}