- allow ()'s and {}'s for now when parsing calls/composite literals

- require ()'s around composite literals at the if/for/switch control clause level
- fixed a nasty bug: passing a value instead of a pointer to a value to an interface
  variable - and not noticing that the value is copied

R=r
OCL=25649
CL=25649

usr/gri/pretty/ast.go

@@ -112,7 +112,8 @@ type (
 	};
 	
 	Call struct {
-		Pos_ int;  // position of "("
+		Pos_ int;  // position of "(" or "{"
+		Tok int;
 		F, Args Expr
 	};
 

usr/gri/pretty/compilation.go

@@ -90,8 +90,7 @@ func (h *errorHandler) ErrorMsg(pos int, msg string) {
 	h.errpos = pos;
 
 	if h.nerrors >= 10 {
-		// TODO enable when done with name convention
-		//sys.Exit(1);
+		sys.Exit(1);
 	}
 }
 
@@ -111,11 +110,6 @@ func (h *errorHandler) Error(pos int, msg string) {
 }
 
 
-func (h *errorHandler) Warning(pos int, msg string) {
-	panic("UNIMPLEMENTED");
-}
-
-
 func Compile(src_file string, flags *Flags) (*AST.Program, int) {
 	src, ok := Platform.ReadSourceFile(src_file);
 	if !ok {
@@ -130,7 +124,7 @@ func Compile(src_file string, flags *Flags) (*AST.Program, int) {
 	scanner.Init(src, &err, true);
 
 	var parser Parser.Parser;
-	parser.Open(&scanner, err, flags.Verbose, flags.Sixg, flags.Deps);
+	parser.Open(&scanner, &err, flags.Verbose, flags.Sixg, flags.Deps);
 
 	prog := parser.ParseProgram();
 

usr/gri/pretty/parser.go

@@ -16,7 +16,6 @@ import (
 
 type ErrorHandler interface {
 	Error(pos int, msg string);
-	Warning(pos int, msg string);
 }
 
 
@@ -39,7 +38,8 @@ type Parser struct {
 	opt_semi bool;  // true if semicolon separator is optional in statement list
 
 	// Nesting levels
-	scope_lev int;  // 0 = global scope, 1 = function scope of global functions, etc.
+	expr_lev int;  // < 0: in control clause, >= 0: in expression
+	scope_lev int;  // 0: global scope, 1: function scope of global functions, etc.
 
 	// Scopes
 	top_scope *SymbolTable.Scope;
@@ -141,6 +141,7 @@ func (P *Parser) Open(scanner *Scanner.Scanner, err ErrorHandler, trace, sixg, d
 
 	P.next();
 	P.scope_lev = 0;
+	P.expr_lev = 0;
 }
 
 
@@ -881,9 +882,11 @@ func (P *Parser) parseFunctionLit() AST.Expr {
 	pos := P.pos;
 	P.expect(Scanner.FUNC);
 	typ := P.parseSignature();
+	P.expr_lev++;
 	P.scope_lev++;
 	body := P.parseBlock(Scanner.LBRACE);
 	P.scope_lev--;
+	P.expr_lev--;
 
 	return &AST.FunctionLit{pos, typ, body};
 }
@@ -901,7 +904,9 @@ func (P *Parser) parseOperand() AST.Expr {
 	case Scanner.LPAREN:
 		pos := P.pos;
 		P.next();
+		P.expr_lev++;
 		x := P.parseExpression(1);
+		P.expr_lev--;
 		P.expect(Scanner.RPAREN);
 		return &AST.Group{pos, x};
 
@@ -962,7 +967,9 @@ func (P *Parser) parseIndex(x AST.Expr) AST.Expr {
 
 	pos := P.pos;
 	P.expect(Scanner.LBRACK);
+	P.expr_lev++;
 	i := P.parseExpression(0);
+	P.expr_lev--;
 	P.expect(Scanner.RBRACK);
 
 	return &AST.Index{pos, x, i};
@@ -971,7 +978,7 @@ func (P *Parser) parseIndex(x AST.Expr) AST.Expr {
 
 func (P *Parser) parseBinaryExpr(prec1 int) AST.Expr
 
-func (P *Parser) parseCompositeElements() AST.Expr {
+func (P *Parser) parseCompositeElements(close int) AST.Expr {
 	x := P.parseExpression(0);
 	if P.tok == Scanner.COMMA {
 		pos := P.pos;
@@ -984,7 +991,7 @@ func (P *Parser) parseCompositeElements() AST.Expr {
 		}
 
 		var last *AST.BinaryExpr;
-		for P.tok != Scanner.RPAREN && P.tok != Scanner.EOF {
+		for P.tok != close && P.tok != Scanner.EOF {
 			y := P.parseExpression(0);
 
 			if singles {
@@ -1018,20 +1025,20 @@ func (P *Parser) parseCompositeElements() AST.Expr {
 }
 
 
-func (P *Parser) parseCallOrCompositeLit(f AST.Expr) AST.Expr {
+func (P *Parser) parseCallOrCompositeLit(f AST.Expr, open, close int) AST.Expr {
 	if P.trace {
 		defer un(trace(P, "CallOrCompositeLit"));
 	}
 
 	pos := P.pos;
-	P.expect(Scanner.LPAREN);
+	P.expect(open);
 	var args AST.Expr;
-	if P.tok != Scanner.RPAREN {
-		args = P.parseCompositeElements();
+	if P.tok != close {
+		args = P.parseCompositeElements(close);
 	}
-	P.expect(Scanner.RPAREN);
+	P.expect(close);
 
-	return &AST.Call{pos, f, args};
+	return &AST.Call{pos, open, f, args};
 }
 
 
@@ -1045,7 +1052,14 @@ func (P *Parser) parsePrimaryExpr() AST.Expr {
 		switch P.tok {
 		case Scanner.PERIOD: x = P.parseSelectorOrTypeGuard(x);
 		case Scanner.LBRACK: x = P.parseIndex(x);
-		case Scanner.LPAREN: x = P.parseCallOrCompositeLit(x);
+		// TODO fix once we have decided on literal/conversion syntax
+		case Scanner.LPAREN: x = P.parseCallOrCompositeLit(x, Scanner.LPAREN, Scanner.RPAREN);
+		case Scanner.LBRACE:
+			if P.expr_lev >= 0 {
+				x = P.parseCallOrCompositeLit(x, Scanner.LBRACE, Scanner.RBRACE);
+			} else {
+				return x;
+			}
 		default:
 			return x;
 		}
@@ -1232,6 +1246,8 @@ func (P *Parser) parseControlClause(isForStat bool) (init AST.Stat, expr AST.Exp
 	}
 
 	if P.tok != Scanner.LBRACE {
+		prev_lev := P.expr_lev;
+		P.expr_lev = -1;	
 		if P.tok != Scanner.SEMICOLON {
 			init = P.parseSimpleStat(isForStat);
 			// TODO check for range clause and exit if found
@@ -1256,6 +1272,7 @@ func (P *Parser) parseControlClause(isForStat bool) (init AST.Stat, expr AST.Exp
 				}
 			}
 		}
+		P.expr_lev = prev_lev;
 	}
 
 	return init, expr, post;

usr/gri/pretty/platform.go

@@ -40,7 +40,7 @@ const (
 func readfile(filename string) ([]byte, *OS.Error) {
 	fd, err := OS.Open(filename, OS.O_RDONLY, 0);
 	if err != nil {
-		return []byte(), err;
+		return []byte{}, err;
 	}
 	var buf [1<<20]byte;
 	n, err1 := IO.Readn(fd, buf);
@@ -67,7 +67,7 @@ func ReadObjectFile(filename string) ([]byte, bool) {
 	if err == nil && len(data) >= len(magic) && string(data[0 : len(magic)]) == magic {
 		return data, true;
 	}
-	return []byte(), false;
+	return []byte{}, false;
 }
 
 

usr/gri/pretty/printer.go

@@ -649,9 +649,12 @@ func (P *Printer) DoIndex(x *AST.Index) {
 
 func (P *Printer) DoCall(x *AST.Call) {
 	P.Expr1(x.F, Scanner.HighestPrec);
-	P.Token(x.Pos_, Scanner.LPAREN);
+	P.Token(x.Pos_, x.Tok);
 	P.Expr(x.Args);
-	P.Token(0, Scanner.RPAREN);
+	switch x.Tok {
+	case Scanner.LPAREN: P.Token(0, Scanner.RPAREN);
+	case Scanner.LBRACE: P.Token(0, Scanner.RBRACE);
+	}
 }
 
 
@@ -946,7 +949,7 @@ func (P *Printer) DoEmptyStat(s *AST.EmptyStat) {
 // Declarations
 
 func (P *Printer) DoBadDecl(d *AST.BadDecl) {
-	unimplemented();
+	P.String(d.Pos, "<BAD DECL>");
 }
 
 

usr/gri/pretty/scanner.go

@@ -620,7 +620,7 @@ loop:
 		S.next();  // always make progress
 		switch ch {
 		case -1: tok = EOF;
-		case '\n': tok, val = COMMENT, []byte('\n');
+		case '\n': tok, val = COMMENT, []byte{'\n'};
 		case '"': tok, val = STRING, S.scanString();
 		case '\'': tok, val = INT, S.scanChar();
 		case '`': tok, val = STRING, S.scanRawString();