fail on parse error invoked by read/1

src/prolog/ast.rs

@@ -1600,7 +1600,10 @@ impl CodePtr {
 #[derive(Clone, PartialEq)]
 pub enum LocalCodePtr {
     DirEntry(usize, ClauseName), // offset, resident module name.
-    TopLevel(usize, usize) // chunk_num, offset.
+    TopLevel(usize, usize), // chunk_num, offset.
+    // DynamicModuleCall(ClauseName, ClauseName, usize)
+    // module name, predicate name and arity.
+    // used for internal, dynamic module calls.
 }
 
 impl LocalCodePtr {