- removed need for lhs field in stat node

- as a result deleted some more code

R=r
OCL=17449
CL=17449

diff --git a/usr/gri/pretty/node.go b/usr/gri/pretty/node.go
index 1fef1c8ff2605b3569dd98aeeb6d635ab71507f5..a465a7856dcdb4440e663cddd9a12a0081c17654 100644 (file)
--- a/usr/gri/pretty/node.go
+++ b/usr/gri/pretty/node.go
@@ -173,7 +173,7 @@ export var BadType = NewType(0, Scanner.ILLEGAL);
 export type Stat struct {
        pos, tok int;
        init, post *Stat;
-       lhs, expr *Expr;
+       expr *Expr;
        block *List;
        decl *Decl;
 }

diff --git a/usr/gri/pretty/parser.go b/usr/gri/pretty/parser.go
index 47f4630f45f1283c98dd39b5058e1546b0121e0e..db3856d86372dceeae02bcd30b752258161ae09f 100644 (file)
--- a/usr/gri/pretty/parser.go
+++ b/usr/gri/pretty/parser.go
@@ -904,13 +904,15 @@ func (P *Parser) ParseSimpleStat() *Node.Stat {
                Scanner.SUB_ASSIGN, Scanner.MUL_ASSIGN, Scanner.QUO_ASSIGN,
                Scanner.REM_ASSIGN, Scanner.AND_ASSIGN, Scanner.OR_ASSIGN,
                Scanner.XOR_ASSIGN, Scanner.SHL_ASSIGN, Scanner.SHR_ASSIGN:
-               s = Node.NewStat(P.pos, P.tok);
+               // assignment
+               pos, tok := P.pos, P.tok;
                P.Next();
-               s.lhs = x;
-               s.expr = P.ParseExpressionList();
-               if l, r := x.len(), s.expr.len(); l > 1 && r > 1 && l != r {
+               y := P.ParseExpressionList();
+               if xl, yl := x.len(), y.len(); xl > 1 && yl > 1 && xl != yl {
                        P.Error(x.pos, "arity of lhs doesn't match rhs");
                }
+               s = Node.NewStat(x.pos, Scanner.EXPRSTAT);
+               s.expr = Node.NewExpr(pos, tok, x, y);
 
        default:
                var pos, tok int;

diff --git a/usr/gri/pretty/printer.go b/usr/gri/pretty/printer.go
index 7a65a8e1d9845f4325778849a5e0de967db26ba7..d66ef8185d44ae3cd2e1789757ebccfe251b8029 100644 (file)
--- a/usr/gri/pretty/printer.go
+++ b/usr/gri/pretty/printer.go
@@ -232,10 +232,10 @@ func (P *Printer) Expr1(x *Node.Expr, prec1 int) {
 
        case Scanner.PERIOD:
                // selector or type guard
-               P.Expr1(x.x, 8);  // 8 == highest precedence
+               P.Expr1(x.x, Scanner.HighestPrec);
                P.String(x.pos, ".");
                if x.y != nil {
-                       P.Expr1(x.y, 8);
+                       P.Expr1(x.y, Scanner.HighestPrec);
                } else {
                        P.String(0, "(");
                        P.Type(x.t);
@@ -244,14 +244,14 @@ func (P *Printer) Expr1(x *Node.Expr, prec1 int) {
                
        case Scanner.LBRACK:
                // index
-               P.Expr1(x.x, 8);
+               P.Expr1(x.x, Scanner.HighestPrec);
                P.String(x.pos, "[");
                P.Expr1(x.y, 0);
                P.String(0, "]");
 
        case Scanner.LPAREN:
                // call
-               P.Expr1(x.x, 8);
+               P.Expr1(x.x, Scanner.HighestPrec);
                P.String(x.pos, "(");
                P.Expr1(x.y, 0);
                P.String(0, ")");
@@ -268,7 +268,7 @@ func (P *Printer) Expr1(x *Node.Expr, prec1 int) {
                if x.x == nil {
                        // unary expression
                        P.Token(x.pos, x.tok);
-                       P.Expr1(x.y, 7);  // 7 == unary operator precedence
+                       P.Expr1(x.y, Scanner.UnaryPrec);
                } else {
                        // binary expression: print ()'s if necessary
                        prec := Scanner.Precedence(x.tok);
@@ -289,7 +289,7 @@ func (P *Printer) Expr1(x *Node.Expr, prec1 int) {
 
 
 func (P *Printer) Expr(x *Node.Expr) {
-       P.Expr1(x, 0);
+       P.Expr1(x, Scanner.LowestPrec);
 }
 
 
@@ -372,18 +372,6 @@ func (P *Printer) Stat(s *Node.Stat) {
                // declaration
                P.Declaration(s.decl, false);
 
-       case Scanner.DEFINE, Scanner.ASSIGN, Scanner.ADD_ASSIGN,
-               Scanner.SUB_ASSIGN, Scanner.MUL_ASSIGN, Scanner.QUO_ASSIGN,
-               Scanner.REM_ASSIGN, Scanner.AND_ASSIGN, Scanner.OR_ASSIGN,
-               Scanner.XOR_ASSIGN, Scanner.SHL_ASSIGN, Scanner.SHR_ASSIGN:
-               // assignment
-               P.Expr(s.lhs);
-               P.Blank();
-               P.Token(s.pos, s.tok);
-               P.Blank();
-               P.Expr(s.expr);
-               P.semi = true;
-
        case Scanner.INC, Scanner.DEC:
                P.Expr(s.expr);
                P.Token(s.pos, s.tok);

diff --git a/usr/gri/pretty/scanner.go b/usr/gri/pretty/scanner.go
index 3af53c0682e293f483223acfbab65ebaca99c255..fcca40d5a7e18513f453747f54ab493b38b9ca09 100644 (file)
--- a/usr/gri/pretty/scanner.go
+++ b/usr/gri/pretty/scanner.go
@@ -210,6 +210,13 @@ export func TokenString(tok int) string {
 }
 
 
+export const (
+       LowestPrec = -1;
+       UnaryPrec = 7;
+       HighestPrec = 8;
+)
+
+
 export func Precedence(tok int) int {
        switch tok {
        case COLON:
@@ -227,7 +234,7 @@ export func Precedence(tok int) int {
        case MUL, QUO, REM, SHL, SHR, AND:
                return 6;
        }
-       return -1;
+       return LowestPrec;
 }