- backward link from objs to containing scope

(first step towards cleaner package handling)
- check that map, function, and channel vars are pointers

R=r
OCL=13690
CL=13690

usr/gri/gosrc/ast.go

@@ -11,27 +11,23 @@ import Universe "universe"
 // ----------------------------------------------------------------------------
 // Expressions
 
-export Expr
+export BinaryExpr
-type Expr interface {
+type BinaryExpr struct {
+	typ_ *Globals.Type;
+	op int;
+	x, y Globals.Expr;
 }
 
 
-export BinaryExpr
+
-type BinaryExpr struct {
+func (x *BinaryExpr) typ() *Globals.Type {
-	typ *Globals.Type;
+	return x.typ_;
-	op int;
-	x, y Expr;
 }
 
 
 // ----------------------------------------------------------------------------
 // Statements
 
-export Stat
-type Stat interface {
-}
-
-
 export Block
 type Block struct {
 	// TODO fill in
@@ -40,7 +36,7 @@ type Block struct {
 
 export IfStat
 type IfStat struct {
-	cond Expr;
+	cond Globals.Expr;
-	then_ Stat;
+	then_ Globals.Stat;
-	else_ Stat;
+	else_ Globals.Stat;
 }

usr/gri/gosrc/decls.go

@@ -6,8 +6,7 @@
 
 package decls
 
-//import "base"
+import "base"
-import base "base"
 import base2 "base"
 
 const c0 int = 0
@@ -53,12 +52,12 @@ type (
 )
 
 type T6 chan int
-type T7 chan<- T6
+type T7 chan<- *T6
-type T8 chan-< T6
+type T8 chan-< *T6
 
 type T9 struct {
   p *T9;
-  q [] map [int] *T9;
+  q [] *map [int] *T9;
   f *func(x, y *T9) *T9;
 }
 
@@ -97,7 +96,7 @@ var v1 float = c1
 var (
   v2 T2;
   v3 struct {
-    f1, f2, f3 M0;
+    f1, f2, f3 *M0;
   }
 )
 
@@ -105,16 +104,19 @@ var (
 func f0() {}
 func f1(a int) {}
 func f2(a, b int, c float) {}
-func f3() bool {}
+func f3() bool { return false; }
 func f4(a int) (z T5, ok bool) {}
-func f5(a, b int, c float) (z T5, ok bool) {}
+func f5(a, b int, c float) (z T5, ok bool) {
+	u, v := 0, 0;
+	return;
+}
 
 
 func (p *T4) m0() {}
 func (p *T4) m1(a int) {}
 func (p *T4) m2(a, b int, c float) {}
-func (p *T4) m3() bool {}
+func (p *T4) m3() bool { return false; }
-func (p *T4) m4(a int) (z T5, ok bool) {}
+func (p *T4) m4(a int) (z T5, ok bool) { return; }
 func (p *T4) m5(a, b int, c float) (z T5, ok bool) {
   L: var x = a;
 }

usr/gri/gosrc/globals.go

@@ -6,7 +6,7 @@ package Globals
 
 
 // The following types should really be in their respective files
-// (object.go, type.go, scope.go, package.go, compilation.go) but
+// (object.go, type.go, scope.go, package.go, compilation.go, etc.) but
 // they refer to each other and we don't know how to handle forward
 // declared pointers across packages yet.
 
@@ -21,6 +21,7 @@ type Object struct {
 	ident string;
 	typ *Type;
 	pnolev int;  // >= 0: package no., <= 0: level, 0: global level of compilation
+	scope *Scope;  // which contains the object
 }
 
 
@@ -33,7 +34,7 @@ type Type struct {
 	len_ int;  // array length, no. of parameters (w/o recv)
 	obj *Object;  // primary type object or NULL
 	key *Type;  // maps
-	elt *Type;  // arrays, maps, channels, pointers
+	elt *Type;  // aliases, arrays, maps, channels, pointers
 	scope *Scope;  // structs, interfaces, functions
 }
 
@@ -94,9 +95,25 @@ type Compilation struct {
 }
 
 
+export Expr
+type Expr interface {
+	typ() *Type;
+	// ... more to come here
+}
+
+
+export Stat
+type Stat interface {
+	// ... more to come here
+}
+
+
 // ----------------------------------------------------------------------------
 // Creation
 
+export Universe_undef_t
+var Universe_undef_t *Type  // initialized by Universe to Universe.undef_t
+
 export NewObject
 func NewObject(pos, kind int, ident string) *Object {
 	obj := new(Object);
@@ -104,8 +121,9 @@ func NewObject(pos, kind int, ident string) *Object {
 	obj.pos = pos;
 	obj.kind = kind;
 	obj.ident = ident;
-	obj.typ = nil;  // Universe::undef_t;  (cyclic import...)
+	obj.typ = Universe_undef_t;
 	obj.pnolev = 0;
+	obj.scope = nil;
 	return obj;
 }
 
@@ -113,7 +131,7 @@ func NewObject(pos, kind int, ident string) *Object {
 export NewType
 func NewType(form int) *Type {
 	typ := new(Type);
-	typ.ref = -1;
+	typ.ref = -1;  // not yet exported
 	typ.form = form;
 	return typ;
 }
@@ -122,7 +140,7 @@ func NewType(form int) *Type {
 export NewPackage;
 func NewPackage(file_name string) *Package {
 	pkg := new(Package);
-	pkg.ref = -1;
+	pkg.ref = -1;  // not yet exported
 	pkg.file_name = file_name;
 	pkg.key = "<the package key>";  // TODO fix this
 	return pkg;
@@ -152,6 +170,22 @@ func NewCompilation(flags *Flags) *Compilation {
 }
 
 
+// ----------------------------------------------------------------------------
+// Object methods
+
+func (obj *Object) Copy() *Object {
+	copy := new(Object);
+	copy.exported = obj.exported;
+	copy.pos = obj.pos;
+	copy.kind = obj.kind;
+	copy.ident = obj.ident;
+	copy.typ = obj.typ;
+	copy.pnolev = obj.pnolev;
+	copy.scope = nil;  // cannot be in the same scope (same ident!)
+	return copy;
+}
+
+
 // ----------------------------------------------------------------------------
 // List methods
 
@@ -239,6 +273,9 @@ func (scope *Scope) Lookup(ident string) *Object {
 	var p *Elem;
 	for p = scope.entries.first; p != nil; p = p.next {
 		if p.obj.ident == ident {
+			if p.obj.scope != scope {
+				panic "incorrect scope for object";
+			}
 			return p.obj;
 		}
 	}
@@ -250,7 +287,11 @@ func (scope *Scope) Insert(obj *Object) {
 	if scope.Lookup(obj.ident) != nil {
 		panic "obj already inserted";
 	}
+	if obj.scope != nil {
+		panic "obj already in a scope";
+	}
 	scope.entries.AddObj(obj);
+	obj.scope = scope;
 }
 
 

usr/gri/gosrc/parser.go

@@ -149,6 +149,7 @@ func (P *Parser) Declare(obj *Globals.Object) {
 
 func MakeFunctionType(sig *Globals.Scope, p0, r0 int, check_recv bool) *Globals.Type {
   // Determine if we have a receiver or not.
+  // TODO do we still need this?
   if p0 > 0 && check_recv {
     // method
 	if p0 != 1 {
@@ -223,7 +224,7 @@ func (P *Parser) DeclareFunc(ident string, typ *Globals.Type) *Globals.Object {
 
 
 func (P *Parser) TryType() *Globals.Type;
-func (P *Parser) ParseExpression();
+func (P *Parser) ParseExpression() Globals.Expr;
 func (P *Parser) TryStatement() bool;
 func (P *Parser) ParseDeclaration();
 
@@ -350,6 +351,32 @@ func (P *Parser) ParseType() *Globals.Type {
 }
 
 
+func (P *Parser) ParseVarType() *Globals.Type {
+	P.Trace("VarType");
+	
+	pos := P.pos;
+	typ := P.ParseType();
+	
+	if P.semantic_checks {
+		switch typ.form {
+		case Type.ARRAY:
+			if P.comp.flags.sixg || typ.len_ >= 0 {
+				break;
+			}
+			// open arrays must be pointers
+			fallthrough;
+			
+		case Type.MAP, Type.CHANNEL, Type.FUNCTION:
+			P.Error(pos, "must be pointer to this type");
+			typ = Universe.bad_t;
+		}
+	}
+		
+	P.Ecart();
+	return typ;
+}
+
+
 func (P *Parser) ParseTypeName() *Globals.Type {
 	P.Trace("TypeName");
 	
@@ -381,7 +408,7 @@ func (P *Parser) ParseArrayType() *Globals.Type {
 		P.ParseExpression();
 	}
 	P.Expect(Scanner.RBRACK);
-	typ.elt = P.ParseType();
+	typ.elt = P.ParseVarType();
 	P.Ecart();
 	
 	return typ;
@@ -403,7 +430,7 @@ func (P *Parser) ParseChannelType() *Globals.Type {
 	default:
 		typ.flags = Type.SEND + Type.RECV;
 	}
-	typ.elt = P.ParseType();
+	typ.elt = P.ParseVarType();
 	P.Ecart();
 	
 	return typ;
@@ -414,7 +441,7 @@ func (P *Parser) ParseVarDeclList() {
 	P.Trace("VarDeclList");
 	
 	list := P.ParseIdentDeclList(Object.VAR);
-	typ := P.ParseType();  // TODO should check completeness of types
+	typ := P.ParseVarType();
 	for p := list.first; p != nil; p = p.next {
 		p.obj.typ = typ;  // TODO should use/have set_type()
 	}
@@ -571,11 +598,13 @@ func (P *Parser) ParseFunctionType() *Globals.Type {
 func (P *Parser) ParseMethodDecl() {
 	P.Trace("MethodDecl");
 	
-	P.ParseIdent();
+	pos := P.pos;
+	ident := P.ParseIdent();
 	P.OpenScope();
 	P.level--;
 	sig := P.top_scope;
-	p0 := 0;
+	// dummy receiver (give it a name so it won't conflict with unnamed result)
+	sig.Insert(Globals.NewObject(pos, Object.VAR, ".recv"));
 	P.ParseParameters();
 	r0 := sig.entries.len_;
 	P.TryResult();
@@ -583,6 +612,10 @@ func (P *Parser) ParseMethodDecl() {
 	P.CloseScope();
 	P.Optional(Scanner.SEMICOLON);
 	
+	obj := Globals.NewObject(pos, Object.FUNC, ident);
+	obj.typ = MakeFunctionType(sig, 1, r0, true);
+	P.Declare(obj);
+	
 	P.Ecart();
 }
 
@@ -614,9 +647,9 @@ func (P *Parser) ParseMapType() *Globals.Type {
 	P.Expect(Scanner.MAP);
 	P.Expect(Scanner.LBRACK);
 	typ := Globals.NewType(Type.MAP);
-	typ.key = P.ParseType();
+	typ.key = P.ParseVarType();
 	P.Expect(Scanner.RBRACK);
-	typ.elt = P.ParseType();
+	typ.elt = P.ParseVarType();
 	P.Ecart();
 	
 	return typ;
@@ -754,14 +787,10 @@ func (P *Parser) ParseBlock(sig *Globals.Scope) {
 	P.OpenScope();
 	if sig != nil {
 		P.level--;
-		// add function parameters to scope
+		// add copies of the formal parameters to the function scope
-		// TODO do we need to make a copy? what if we change obj fields?
 		scope := P.top_scope;
 		for p := sig.entries.first; p != nil; p = p.next {
-			if p.obj.pnolev != P.level {
+			scope.Insert(p.obj.Copy())
-				panic "incorrect level";
-			}
-			scope.Insert(p.obj)
 		}
 	}
 	if P.tok != Scanner.RBRACE && P.tok != Scanner.SEMICOLON {
@@ -798,7 +827,7 @@ func (P *Parser) ParseExpressionList() *Globals.List {
 }
 
 
-func (P *Parser) ParseNew() {
+func (P *Parser) ParseNew() Globals.Expr {
 	P.Trace("New");
 	
 	P.Expect(Scanner.NEW);
@@ -811,16 +840,18 @@ func (P *Parser) ParseNew() {
 	P.Expect(Scanner.RPAREN);
 	
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseFunctionLit() {
+func (P *Parser) ParseFunctionLit() Globals.Expr {
 	P.Trace("FunctionLit");
 	
 	typ := P.ParseFunctionType();
 	P.ParseBlock(typ.scope);
 	
 	P.Ecart();
+	return nil;
 }
 
 
@@ -847,16 +878,17 @@ func (P *Parser) ParseExpressionPairList() {
 }
 
 
-func (P *Parser) ParseBuiltinCall() {
+func (P *Parser) ParseBuiltinCall() Globals.Expr {
 	P.Trace("BuiltinCall");
 	
 	P.ParseExpressionList();  // TODO should be optional
 	
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseCompositeLit(typ *Globals.Type) {
+func (P *Parser) ParseCompositeLit(typ *Globals.Type) Globals.Expr {
 	P.Trace("CompositeLit");
 	
 	// TODO I think we should use {} instead of () for
@@ -894,10 +926,11 @@ func (P *Parser) ParseCompositeLit(typ *Globals.Type) {
 	P.Expect(paren);
 
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseOperand(pos int, ident string) {
+func (P *Parser) ParseOperand(pos int, ident string) Globals.Expr {
 	P.Trace("Operand");
 
 	if pos < 0 && P.tok == Scanner.IDENT {
@@ -954,10 +987,11 @@ func (P *Parser) ParseOperand(pos int, ident string) {
 	
 exit:
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseSelectorOrTypeAssertion() {
+func (P *Parser) ParseSelectorOrTypeAssertion() Globals.Expr {
 	P.Trace("SelectorOrTypeAssertion");
 	
 	P.Expect(Scanner.PERIOD);
@@ -970,10 +1004,11 @@ func (P *Parser) ParseSelectorOrTypeAssertion() {
 	}
 	
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseIndexOrSlice() {
+func (P *Parser) ParseIndexOrSlice() Globals.Expr {
 	P.Trace("IndexOrSlice");
 	
 	P.Expect(Scanner.LBRACK);
@@ -985,10 +1020,11 @@ func (P *Parser) ParseIndexOrSlice() {
 	P.Expect(Scanner.RBRACK);
 	
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParseCall() {
+func (P *Parser) ParseCall() Globals.Expr {
 	P.Trace("Call");
 	
 	P.Expect(Scanner.LPAREN);
@@ -998,10 +1034,11 @@ func (P *Parser) ParseCall() {
 	P.Expect(Scanner.RPAREN);
 	
 	P.Ecart();
+	return nil;
 }
 
 
-func (P *Parser) ParsePrimaryExpr(pos int, ident string) AST.Expr {
+func (P *Parser) ParsePrimaryExpr(pos int, ident string) Globals.Expr {
 	P.Trace("PrimaryExpr");
 	
 	P.ParseOperand(pos, ident);
@@ -1037,7 +1074,7 @@ func (P *Parser) ParsePrimaryExprList() {
 }
 
 
-func (P *Parser) ParseUnaryExpr() AST.Expr {
+func (P *Parser) ParseUnaryExpr() Globals.Expr {
 	P.Trace("UnaryExpr");
 	
 	switch P.tok {
@@ -1080,10 +1117,10 @@ func Precedence(tok int) int {
 }
 
 
-func (P *Parser) ParseBinaryExpr(pos int, ident string, prec1 int) AST.Expr {
+func (P *Parser) ParseBinaryExpr(pos int, ident string, prec1 int) Globals.Expr {
 	P.Trace("BinaryExpr");
 	
-	var x AST.Expr;
+	var x Globals.Expr;
 	if pos >= 0 {
 		x = P.ParsePrimaryExpr(pos, ident);
 	} else {
@@ -1092,7 +1129,7 @@ func (P *Parser) ParseBinaryExpr(pos int, ident string, prec1 int) AST.Expr {
 	for prec := Precedence(P.tok); prec >= prec1; prec-- {
 		for Precedence(P.tok) == prec {
 			e := new(AST.BinaryExpr);
-			e.typ = Universe.undef_t;  // TODO fix this
+			e.typ_ = Universe.undef_t;  // TODO fix this
 			e.op = P.tok;  // TODO should we use tokens or separate operator constants?
 			e.x = x;
 			P.Next();
@@ -1102,29 +1139,34 @@ func (P *Parser) ParseBinaryExpr(pos int, ident string, prec1 int) AST.Expr {
 	}
 	
 	P.Ecart();
+	return x;
 }
 
 
 // Expressions where the first token may be an identifier which has already
 // been consumed. If the identifier is present, pos is the identifier position,
 // otherwise pos must be < 0 (and ident is ignored).
-func (P *Parser) ParseIdentExpression(pos int, ident string) {
+func (P *Parser) ParseIdentExpression(pos int, ident string) Globals.Expr {
 	P.Trace("IdentExpression");
 	indent := P.indent;
 	
-	P.ParseBinaryExpr(pos, ident, 1);
+	x := P.ParseBinaryExpr(pos, ident, 1);
 	
 	if indent != P.indent {
 		panic "imbalanced tracing code (Expression)";
 	}
 	P.Ecart();
+	return x;
 }
 
 
-func (P *Parser) ParseExpression() {
+func (P *Parser) ParseExpression() Globals.Expr {
 	P.Trace("Expression");
-	P.ParseIdentExpression(-1, "");
+	
+	x := P.ParseIdentExpression(-1, "");
+
 	P.Ecart();
+	return x;
 }
 
 
@@ -1280,8 +1322,10 @@ func (P *Parser) ParseSimpleStat() {
 
 func (P *Parser) ParseGoStat() {
 	P.Trace("GoStat");
+	
 	P.Expect(Scanner.GO);
 	P.ParseExpression();
+	
 	P.Ecart();
 }
 
@@ -1666,9 +1710,9 @@ func (P *Parser) ParseVarSpec(exported bool) {
 		P.Next();
 		P.ParseExpressionList();
 	} else {
-		typ := P.ParseType();
+		typ := P.ParseVarType();
 		for p := list.first; p != nil; p = p.next {
-			p.obj.typ = typ;  // TODO should use/have set_type()!
+			p.obj.typ = typ;
 		}
 		if P.tok == Scanner.ASSIGN {
 			P.Next();

usr/gri/gosrc/printer.go

@@ -79,7 +79,7 @@ func (P *Printer) PrintSignature(typ *Globals.Type, fun *Globals.Object) {
 	
 	if fun != nil {
 		P.PrintObject(fun);
-		print " ";
+		//print " ";
 	} else if p0 > 0 {
 		print ". ";
 	}
@@ -94,10 +94,9 @@ func (P *Printer) PrintSignature(typ *Globals.Type, fun *Globals.Object) {
 
 
 func (P *Printer) PrintIndent() {
-	const scale = 4;
 	print "\n";
-	for i := P.level * scale; i > 0; i-- {
+	for i := P.level; i > 0; i-- {
-		print " ";
+		print "\t";
 	}
 }
 

usr/gri/gosrc/universe.go

@@ -109,6 +109,7 @@ func init() {
 	
 	// Interal types
 	undef_t = Globals.NewType(Type.UNDEF);
+	Globals.Universe_undef_t = undef_t;
 	bad_t = Globals.NewType(Type.BAD);
 	nil_t = DeclType(Type.NIL, "nil", 8);
 	

usr/gri/gosrc/verifier.go

@@ -25,10 +25,6 @@ func VerifyObject(obj *Globals.Object, pnolev int);
 
 
 func VerifyType(typ *Globals.Type) {
-	if typ == nil {
-		return;  // see Globals.NewObject
-	}
-	
 	if typ.obj != nil {
 		VerifyObject(typ.obj, 0);
 	}