clean up support for recursive calls, add support for (and protection of) built-in predicates.

2017-08-02 17:38:12 -06:00
parent 3aa8780086
commit 315c748c31
6 changed files with 131 additions and 110 deletions
--- a/src/prolog/codegen.rs
+++ b/src/prolog/codegen.rs
@@ -14,7 +14,7 @@ pub struct CodeGenerator<'a, TermMarker> {
 }

 pub enum EvalSession<'a> {
-    EntryFailure,
+    EntryFailure(String),
    EntrySuccess,
    InitialQuerySuccess(AllocVarDict<'a>, HeapVarDict<'a>),
    QueryFailure,