Experiments with "export":

Allow "export" keyword in front of a declaration. Semantics:
export *top-level* identifiers declared (but not the fields
of a struct type for instance).

R=r
OCL=13464
CL=13464

diff --git a/usr/gri/gosrc/parser.go b/usr/gri/gosrc/parser.go
index 4c9f70ffdf202bbd2de2c0b1ce0d87be13a1000b..566e5176acaeac754109bd33c90ef3fd26d0bc7f 100644 (file)
--- a/usr/gri/gosrc/parser.go
+++ b/usr/gri/gosrc/parser.go
@@ -971,8 +971,9 @@ func (P *Parser) ParseBinaryExpr(pos int, ident string, prec1 int) AST.Expr {
 }
 
 
-// Expressions where the first token may be an
-// identifier that has already been consumed.
+// 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) {
        P.Trace("IdentExpression");
        indent := P.indent;
@@ -1456,13 +1457,14 @@ func (P *Parser) ParseImportDecl() {
 }
 
 
-func (P *Parser) ParseConstSpec() {
+func (P *Parser) ParseConstSpec(exported bool) {
        P.Trace("ConstSpec");
        
        list := P.ParseIdentDeclList(Object.CONST);
        typ := P.TryType();
        if typ != nil {
                for p := list.first; p != nil; p = p.next {
+                       p.obj.mark = exported;
                        p.obj.typ = typ;  // TODO should use/have set_type()!
                }
        }
@@ -1475,28 +1477,28 @@ func (P *Parser) ParseConstSpec() {
 }
 
 
-func (P *Parser) ParseConstDecl() {
+func (P *Parser) ParseConstDecl(exported bool) {
        P.Trace("ConstDecl");
        
        P.Expect(Scanner.CONST);
        if P.tok == Scanner.LPAREN {
                P.Next();
                for P.tok == Scanner.IDENT {
-                       P.ParseConstSpec();
+                       P.ParseConstSpec(exported);
                        if P.tok != Scanner.RPAREN {
                                P.Expect(Scanner.SEMICOLON);
                        }
                }
                P.Next();
        } else {
-               P.ParseConstSpec();
+               P.ParseConstSpec(exported);
        }
        
        P.Ecart();
 }
 
 
-func (P *Parser) ParseTypeSpec() {
+func (P *Parser) ParseTypeSpec(exported bool) {
        P.Trace("TypeSpec");
        
        pos := P.pos;
@@ -1510,6 +1512,7 @@ func (P *Parser) ParseTypeSpec() {
                }
        } else {
                obj = Globals.NewObject(pos, Object.TYPE, ident);
+               obj.mark = exported;
                obj.typ = Universe.undef_t;  // TODO fix this
                P.top_scope.Insert(obj);
        }
@@ -1527,28 +1530,28 @@ func (P *Parser) ParseTypeSpec() {
 }
 
 
-func (P *Parser) ParseTypeDecl() {
+func (P *Parser) ParseTypeDecl(exported bool) {
        P.Trace("TypeDecl");
        
        P.Expect(Scanner.TYPE);
        if P.tok == Scanner.LPAREN {
                P.Next();
                for P.tok == Scanner.IDENT {
-                       P.ParseTypeSpec();
+                       P.ParseTypeSpec(exported);
                        if P.tok != Scanner.RPAREN {
                                P.Expect(Scanner.SEMICOLON);
                        }
                }
                P.Next();
        } else {
-               P.ParseTypeSpec();
+               P.ParseTypeSpec(exported);
        }
        
        P.Ecart();
 }
 
 
-func (P *Parser) ParseVarSpec() {
+func (P *Parser) ParseVarSpec(exported bool) {
        P.Trace("VarSpec");
        
        list := P.ParseIdentDeclList(Object.VAR);
@@ -1570,28 +1573,28 @@ func (P *Parser) ParseVarSpec() {
 }
 
 
-func (P *Parser) ParseVarDecl() {
+func (P *Parser) ParseVarDecl(exported bool) {
        P.Trace("VarDecl");
        
        P.Expect(Scanner.VAR);
        if P.tok == Scanner.LPAREN {
                P.Next();
                for P.tok == Scanner.IDENT {
-                       P.ParseVarSpec();
+                       P.ParseVarSpec(exported);
                        if P.tok != Scanner.RPAREN {
                                P.Expect(Scanner.SEMICOLON);
                        }
                }
                P.Next();
        } else {
-               P.ParseVarSpec();
+               P.ParseVarSpec(exported);
        }
        
        P.Ecart();
 }
 
 
-func (P *Parser) ParseFuncDecl() {
+func (P *Parser) ParseFuncDecl(exported bool) {
        P.Trace("FuncDecl");
        
        P.Expect(Scanner.FUNC);
@@ -1612,7 +1615,7 @@ func (P *Parser) ParseExportDecl() {
        
        // TODO this needs to be clarified - the current syntax is
        // "everything goes" - sigh...
-       P.Expect(Scanner.EXPORT);
+       //P.Expect(Scanner.EXPORT);
        has_paren := false;
        if P.tok == Scanner.LPAREN {
                P.Next();
@@ -1632,27 +1635,40 @@ func (P *Parser) ParseExportDecl() {
 
 func (P *Parser) ParseDeclaration() {
        P.Trace("Declaration");
-       
        indent := P.indent;
+       
+       exported := false;
+       if P.tok == Scanner.EXPORT {
+               P.Next();
+               exported = true;
+       }
        switch P.tok {
        case Scanner.CONST:
-               P.ParseConstDecl();
+               P.ParseConstDecl(exported);
        case Scanner.TYPE:
-               P.ParseTypeDecl();
+               P.ParseTypeDecl(exported);
        case Scanner.VAR:
-               P.ParseVarDecl();
+               P.ParseVarDecl(exported);
        case Scanner.FUNC:
-               P.ParseFuncDecl();
+               P.ParseFuncDecl(exported);
        case Scanner.EXPORT:
+               if exported {
+                       P.Error(P.pos, "cannot mark export declaration for export");
+               }
+               P.Next();
                P.ParseExportDecl();
        default:
-               P.Error(P.pos, "declaration expected");
-               P.Next();  // make progress
+               if exported && (P.tok == Scanner.IDENT || P.tok == Scanner.LPAREN) {
+                       P.ParseExportDecl();
+               } else {
+                       P.Error(P.pos, "declaration expected");
+                       P.Next();  // make progress
+               }
        }
+       
        if indent != P.indent {
                panic "imbalanced tracing code (Declaration)"
        }
-       
        P.Ecart();
 }
 

diff --git a/usr/gri/gosrc/scanner.go b/usr/gri/gosrc/scanner.go
index c209f16952d99367a771329e7c0e1890d0fd68a3..0f968f6c2eca87e7fe6e150f07fd5cb948c93ed3 100644 (file)
--- a/usr/gri/gosrc/scanner.go
+++ b/usr/gri/gosrc/scanner.go
@@ -387,8 +387,8 @@ func Init() {
          Keywords[TokenName(i)] = i;
        }
        
-       // r doesn't want column information in error messages...
-       VerboseMsgs = !IsUser("r");
+       // Provide column information in error messages for gri only...
+       VerboseMsgs = IsUser("gri");
 }