add top level exception reporting, exceptions for call/N.

2017-08-17 18:20:58 -06:00
parent 1a7edc2d13
commit 02c0f1cf56
5 changed files with 165 additions and 95 deletions
--- a/src/prolog/codegen.rs
+++ b/src/prolog/codegen.rs
@@ -18,6 +18,7 @@ pub enum EvalSession<'a> {
    EntrySuccess,
    InitialQuerySuccess(AllocVarDict<'a>, HeapVarDict<'a>),
    QueryFailure,
+    QueryFailureWithException(String),
    SubsequentQuerySuccess,
 }