@@ -59,11 +59,11 @@
 	e.addPrimitive("_isstr", ValueLayer,
 		(Value v){return new IntValue(cast(StrValue)v !is null);} );
 	e.addPrimitive("_isfun", ValueLayer,
 		(Value v){return new IntValue(cast(FunValue)v !is null);} );
-	e.addPrimitive("_isundefined", ValueLayer,
+	e.addPrimitive("_isbot", ValueLayer,
 		(Value v){return new IntValue(cast(BottomValue)v !is null);} );
-	e.addPrimitive("_istable", ValueLayer,
+	e.addPrimitive("_istbl", ValueLayer,
 		(Value v){return new IntValue(cast(Table)v !is null);} );
 	// table
 	e.addPrimitive(".", ValueLayer, (Table t, StrValue s){
 		if( t.has(s.data, ValueLayer) )