- changed my scanner/parser to accept new channel syntax

R=r
OCL=15439
CL=15439

usr/gri/gosrc/decls.go

@@ -56,8 +56,8 @@ type (
 export type M5 (p T5) . (a, b int, c float) (z T5, ok bool);
 
 type T6 chan int
-type T7 chan<- *T6
-type T8 chan-< *T6
+type T7 <- chan *T6
+type T8 chan <- *T6
 
 type T9 struct {
 	p *T9;

usr/gri/gosrc/parser.go

@@ -430,8 +430,8 @@ func (P *Parser) ParseArrayType() *Globals.Type {
 	}
 	P.Expect(Scanner.RBRACK);
 	typ.elt = P.ParseVarType();
-	P.Ecart();
 
+	P.Ecart();	
 	return typ;
 }
 
@@ -439,21 +439,23 @@ func (P *Parser) ParseArrayType() *Globals.Type {
 func (P *Parser) ParseChannelType() *Globals.Type {
 	P.Trace("ChannelType");
 	
-	P.Expect(Scanner.CHAN);
 	typ := Globals.NewType(Type.CHANNEL);
-	switch P.tok {
-	case Scanner.SEND:
-		typ.flags = Type.SEND;
+	if P.tok == Scanner.CHAN {
 		P.Next();
-	case Scanner.RECV:
-		typ.flags = Type.RECV;
+		if P.tok == Scanner.ARROW {
+			typ.flags = Type.SEND;
 			P.Next();
-	default:
+		} else {
 			typ.flags = Type.SEND + Type.RECV;
 		}
+	} else {
+		P.Expect(Scanner.ARROW);
+		P.Expect(Scanner.CHAN);
+		typ.flags = Type.RECV;
+	}
 	typ.elt = P.ParseVarType();
-	P.Ecart();
 
+	P.Ecart();	
 	return typ;
 }
 
@@ -797,7 +799,7 @@ func (P *Parser) TryType() *Globals.Type {
 	switch P.tok {
 	case Scanner.IDENT: typ = P.ParseTypeName();
 	case Scanner.LBRACK: typ = P.ParseArrayType();
-	case Scanner.CHAN: typ = P.ParseChannelType();
+	case Scanner.CHAN, Scanner.ARROW: typ = P.ParseChannelType();
 	case Scanner.INTERFACE: typ = P.ParseInterfaceType();
 	case Scanner.LPAREN: typ = P.ParseFunctionType();
 	case Scanner.MAP: typ = P.ParseMapType();
@@ -946,25 +948,14 @@ func (P *Parser) ParseExpressionPairList(list *Globals.List) {
 func (P *Parser) ParseCompositeLit(typ *Globals.Type) Globals.Expr {
 	P.Trace("CompositeLit");
 	
-	// TODO I think we should use {} instead of () for
-	// composite literals to syntactically distinguish
-	// them from conversions. For now: allow both.
-	var paren int;
-	if P.tok == Scanner.LPAREN {
-		P.Next();
-		paren = Scanner.RPAREN;
-	} else {
 	P.Expect(Scanner.LBRACE);
-		paren = Scanner.RBRACE;
-	}
-	
 	// TODO: should allow trailing ','
 	list := Globals.NewList();
-	if P.tok != paren {
+	if P.tok != Scanner.RBRACE {
 		list.AddExpr(P.ParseExpression());
 		if P.tok == Scanner.COMMA {
 			P.Next();
-			if P.tok != paren {
+			if P.tok != Scanner.RBRACE {
 				P.ParseExpressionList(list);
 			}
 		} else if P.tok == Scanner.COLON {
@@ -972,14 +963,13 @@ func (P *Parser) ParseCompositeLit(typ *Globals.Type) Globals.Expr {
 			list.AddExpr(P.ParseExpression());
 			if P.tok == Scanner.COMMA {
 				P.Next();
-				if P.tok != paren {
+				if P.tok != Scanner.RBRACE {
 					P.ParseExpressionPairList(list);
 				}
 			}
 		}
 	}
-
-	P.Expect(paren);
+	P.Expect(Scanner.RBRACE);
 
 	P.Ecart();
 	return nil;
@@ -1228,7 +1218,7 @@ func (P *Parser) ParseUnaryExpr() Globals.Expr {
 	case Scanner.NOT: fallthrough;
 	case Scanner.XOR: fallthrough;
 	case Scanner.MUL: fallthrough;
-	case Scanner.RECV: fallthrough;
+	case Scanner.ARROW: fallthrough;
 	case Scanner.AND:
 		P.Next();
 		P.ParseUnaryExpr();
@@ -1249,7 +1239,7 @@ func Precedence(tok int) int {
 		return 1;
 	case Scanner.LAND:
 		return 2;
-	case Scanner.SEND, Scanner.RECV:
+	case Scanner.ARROW:
 		return 3;
 	case Scanner.EQL, Scanner.NEQ, Scanner.LSS, Scanner.LEQ, Scanner.GTR, Scanner.GEQ:
 		return 4;
@@ -1702,7 +1692,7 @@ func (P *Parser) TryStatement() bool {
 	case Scanner.FUNC:
 		// for now we do not allow local function declarations
 		fallthrough;
-	case Scanner.MUL, Scanner.SEND, Scanner.RECV, Scanner.IDENT, Scanner.LPAREN:
+	case Scanner.MUL, Scanner.ARROW, Scanner.IDENT, Scanner.LPAREN:
 		P.ParseSimpleStat();
 	case Scanner.GO:
 		P.ParseGoStat();

usr/gri/gosrc/scanner.go

@@ -54,8 +54,7 @@ export const (
 	SHL;
 	SHR;
 	
-	SEND;
-	RECV;
+	ARROW;
 
 	ADD_ASSIGN;
 	SUB_ASSIGN;
@@ -163,8 +162,7 @@ export func TokenName(tok int) string {
 	case SHL: return "<<";
 	case SHR: return ">>";
 	
-	case SEND: return "-<";
-	case RECV: return "<-";
+	case ARROW: return "<-";
 
 	case ADD_ASSIGN: return "+=";
 	case SUB_ASSIGN: return "-=";
@@ -740,13 +738,7 @@ func (S *Scanner) Scan() (tok, pos int, val string) {
 		case '{': tok = LBRACE;
 		case '}': tok = RBRACE;
 		case '+': tok = S.Select3(ADD, ADD_ASSIGN, '+', INC);
-		case '-':
-			if S.ch == '<' {
-				S.Next();
-				tok = SEND;
-			} else {
-				tok = S.Select3(SUB, SUB_ASSIGN, '-', DEC);
-			}
+		case '-': tok = S.Select3(SUB, SUB_ASSIGN, '-', DEC);
 		case '*': tok = S.Select2(MUL, MUL_ASSIGN);
 		case '/':
 			if S.ch == '/' || S.ch == '*' {
@@ -761,7 +753,7 @@ func (S *Scanner) Scan() (tok, pos int, val string) {
 		case '<':
 			if S.ch == '-' {
 				S.Next();
-				tok = RECV;
+				tok = ARROW;
 			} else {
 				tok = S.Select4(LSS, LEQ, '<', SHL, SHL_ASSIGN);
 			}
@@ -791,7 +783,7 @@ func (S *Scanner) Server(c *chan *Token) {
 	for {
 		t := new(Token);
 		t.tok, t.pos, t.val = S.Scan();
-		c -< t;
+		c <- t;
 		if t.tok == EOF {
 			break;
 		}