enhance __traits(identifier) to pick the identifier out of a paramete…

…r list tuple
dlang · Nov 4, 2012 · b3b4940 · b3b4940 · braddr · Nov 4, 2012
1 parent f018414
commit b3b4940
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Showing 5 changed files with 44 additions and 10 deletions.
diff --git a/src/mars.h b/src/mars.h
@@ -408,6 +408,7 @@ enum DYNCAST
     DYNCAST_TYPE,
     DYNCAST_IDENTIFIER,
     DYNCAST_TUPLE,
+    DYNCAST_PARAMETER,
 };
 
 enum MATCH

diff --git a/src/mtype.h b/src/mtype.h
@@ -983,6 +983,7 @@ struct Parameter : Object
     Parameter *syntaxCopy();
     Type *isLazyArray();
     void toDecoBuffer(OutBuffer *buf);
+    int dyncast() { return DYNCAST_PARAMETER; } // kludge for template.isType()
     static Parameters *arraySyntaxCopy(Parameters *args);
     static char *argsTypesToChars(Parameters *args, int varargs);
     static void argsCppMangle(OutBuffer *buf, CppMangleState *cms, Parameters *arguments, int varargs);

diff --git a/src/template.c b/src/template.c
@@ -79,6 +79,14 @@ Tuple *isTuple(Object *o)
     return (Tuple *)o;
 }
 
+Parameter *isParameter(Object *o)
+{
+    //return dynamic_cast<Parameter *>(o);
+    if (!o || o->dyncast() != DYNCAST_PARAMETER)
+        return NULL;
+    return (Parameter *)o;
+}
+
 /**************************************
  * Is this Object an error?
  */
@@ -127,6 +135,9 @@ Type *getType(Object *o)
 
 Dsymbol *getDsymbol(Object *oarg)
 {
+    //printf("getDsymbol()\n");
+    //printf("e %p s %p t %p v %p\n", isExpression(oarg), isDsymbol(oarg), isType(oarg), isTuple(oarg));
+
     Dsymbol *sa;
     Expression *ea = isExpression(oarg);
     if (ea)
@@ -5076,6 +5087,7 @@ void TemplateInstance::semanticTiargs(Scope *sc)
 /**********************************
  * Input:
  *      flags   1: replace const variables with their initializers
+ *              2: don't devolve Parameter to Type
  */
 
 void TemplateInstance::semanticTiargs(Loc loc, Scope *sc, Objects *tiargs, int flags)
@@ -5136,7 +5148,10 @@ void TemplateInstance::semanticTiargs(Loc loc, Scope *sc, Objects *tiargs, int f
                     {   tiargs->reserve(dim);
                         for (size_t i = 0; i < dim; i++)
                         {   Parameter *arg = (*tt->arguments)[i];
-                            tiargs->insert(j + i, arg->type);
+                            if (flags & 2 && arg->ident)
+                                tiargs->insert(j + i, arg);
+                            else
+                                tiargs->insert(j + i, arg->type);
                         }
                     }
                     j--;
@@ -5213,11 +5228,14 @@ void TemplateInstance::semanticTiargs(Loc loc, Scope *sc, Objects *tiargs, int f
         }
         else if (sa)
         {
-		Lsa:
+                Lsa:
             TemplateDeclaration *td = sa->isTemplateDeclaration();
             if (td && !td->semanticRun && td->literal)
                 td->semantic(sc);
         }
+        else if (isParameter(o))
+        {
+        }
         else
         {
             assert(0);

diff --git a/src/template.h b/src/template.h
@@ -36,6 +36,7 @@ struct Expression;
 struct AliasDeclaration;
 struct FuncDeclaration;
 struct HdrGenState;
+struct Parameter;
 enum MATCH;
 enum PASS;
 
@@ -368,6 +369,7 @@ Expression *isExpression(Object *o);
 Dsymbol *isDsymbol(Object *o);
 Type *isType(Object *o);
 Tuple *isTuple(Object *o);
+Parameter *isParameter(Object *o);
 int arrayObjectIsError(Objects *args);
 int isError(Object *o);
 Type *getType(Object *o);

diff --git a/src/traits.c b/src/traits.c
@@ -190,20 +190,32 @@ Expression *TraitsExp::semantic(Scope *sc)
     else if (ident == Id::identifier)
     {   // Get identifier for symbol as a string literal
 
-        // Specify 0 for the flags argument to semanticTiargs() so that
-        // a symbol should not be folded to a constant.
-        TemplateInstance::semanticTiargs(loc, sc, args, 0);
+        /* Specify 0 for bit 0 of the flags argument to semanticTiargs() so that
+         * a symbol should not be folded to a constant.
+         * Bit 1 means don't convert Parameter to Type if Parameter has an identifier
+         */
+        TemplateInstance::semanticTiargs(loc, sc, args, 2);
 
         if (dim != 1)
             goto Ldimerror;
         Object *o = (*args)[0];
-        Dsymbol *s = getDsymbol(o);
-        if (!s || !s->ident)
+        Parameter *po = isParameter(o);
+        Identifier *id;
+        if (po)
+        {   id = po->ident;
+            assert(id);
+        }
+        else
         {
-            error("argument %s has no identifier", o->toChars());
-            goto Lfalse;
+            Dsymbol *s = getDsymbol(o);
+            if (!s || !s->ident)
+            {
+                error("argument %s has no identifier", o->toChars());
+                goto Lfalse;
+            }
+            id = s->ident;
         }
-        StringExp *se = new StringExp(loc, s->ident->toChars());
+        StringExp *se = new StringExp(loc, id->toChars());
         return se->semantic(sc);
     }
     else if (ident == Id::parent)