Commit de9cf528 authored by Robert Griesemer's avatar Robert Griesemer

- receiver syntax verification

- removed left-over panic() call
- fixed a couple of bugs

R=r
OCL=26856
CL=26856
parent 75a5d6cd
......@@ -1046,7 +1046,8 @@ func (p *parser) parseCompositeLit(typ ast.Expr) ast.Expr {
// TODO apply these make functions more thoroughly
// (all uses of parseExpression)
// (all uses of parseExpression; also should call
// them something better - verifyX?)
// makeExpr makes sure x is an expression and not a type.
func (p *parser) makeExpr(x ast.Expr) ast.Expr {
......@@ -1061,7 +1062,7 @@ func (p *parser) makeExpr(x ast.Expr) ast.Expr {
case *ast.StringList: return x;
case *ast.FunctionLit: return x;
case *ast.CompositeLit: return x;
case *ast.ParenExpr: return p.makeExpr(t.X);
case *ast.ParenExpr: p.makeExpr(t.X); return x;
case *ast.SelectorExpr: return x;
case *ast.IndexExpr: return x;
case *ast.SliceExpr: return x;
......@@ -1074,34 +1075,42 @@ func (p *parser) makeExpr(x ast.Expr) ast.Expr {
// all other nodes are not proper expressions
p.error_expected(x.Pos(), "expression");
panic();
return &ast.BadExpr{x.Pos()};
}
// makeType makes sure x is a type and not an expression.
func (p *parser) makeType(x ast.Expr) ast.Expr {
// makeTypeName makes sure that x is type name.
func (p *parser) makeTypeName(x ast.Expr) ast.Expr {
// TODO should provide predicate in AST nodes
switch t := x.(type) {
case *ast.BadExpr: return x;
case *ast.Ident: return x;
case *ast.ParenExpr: return p.makeType(t.X);
case *ast.ArrayType:
if len, is_ellipsis := t.Len.(*ast.Ellipsis); is_ellipsis {
p.error(len.Pos(), "expected array length, found '...'");
return &ast.BadExpr{x.Pos()};
case *ast.ParenExpr: p.makeTypeName(t.X); return x; // TODO should (TypeName) be illegal?
case *ast.SelectorExpr: p.makeTypeName(t.X); return x;
}
return x;
// all other nodes are not type names
p.error_expected(x.Pos(), "type name");
return &ast.BadExpr{x.Pos()};
}
// makeCompositeLitType makes sure x is a legal composite literal type.
func (p *parser) makeCompositeLitType(x ast.Expr) ast.Expr {
// TODO should provide predicate in AST nodes
switch t := x.(type) {
case *ast.BadExpr: return x;
case *ast.Ident: return x;
case *ast.ParenExpr: p.makeCompositeLitType(t.X); return x;
case *ast.SelectorExpr: p.makeTypeName(t.X); return x;
case *ast.ArrayType: return x;
case *ast.SliceType: return x;
case *ast.StructType: return x;
case *ast.FunctionType: return x;
case *ast.InterfaceType: return x;
case *ast.MapType: return x;
case *ast.ChannelType: return x;
}
// all other nodes are not types
p.error_expected(x.Pos(), "type");
// all other nodes are not legal composite literal types
p.error_expected(x.Pos(), "composite literal type");
return &ast.BadExpr{x.Pos()};
}
......@@ -1136,7 +1145,7 @@ func (p *parser) parsePrimaryExpr() ast.Expr {
case token.LPAREN: x = p.parseCallOrConversion(p.makeExprOrType(x));
case token.LBRACE:
if p.expr_lev >= 0 {
x = p.parseCompositeLit(x);
x = p.parseCompositeLit(p.makeCompositeLitType(x));
} else {
return p.makeExprOrType(x);
}
......@@ -1748,6 +1757,33 @@ func (p *parser) parseDecl(keyword int) ast.Decl {
}
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.error_expected(pos, "exactly one receiver");
return &ast.Field{nil, nil, &ast.BadExpr{noPos}, nil};
}
recv := par[0];
// recv type must be TypeName or *TypeName
base := recv.Type;
if ptr, is_ptr := base.(*ast.StarExpr); is_ptr {
base = ptr.X;
}
p.makeTypeName(base);
return recv;
}
func (p *parser) parseFunctionDecl() *ast.FuncDecl {
if p.trace {
defer un(trace(p, "FunctionDecl"));
......@@ -1758,13 +1794,7 @@ func (p *parser) parseFunctionDecl() *ast.FuncDecl {
var recv *ast.Field;
if p.tok == token.LPAREN {
pos := p.pos;
tmp := p.parseParameters(false);
if len(tmp) == 1 {
recv = tmp[0];
} else {
p.error_expected(pos, "exactly one receiver");
}
recv = p.parseReceiver();
}
ident := p.parseIdent();
......
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