1. the default for the default equality/absurd/true/false URIs used to be

[helm.git] / components / tactics / equalityTactics.ml

diff --git a/components/tactics/equalityTactics.ml b/components/tactics/equalityTactics.ml
index cca2c1a5902b9256736dd8b1001abe42c1d3ea22..b1727fb7d401d35fa761a2dd9c4cbb3540c9bf6e 100644 (file)
--- a/components/tactics/equalityTactics.ml
+++ b/components/tactics/equalityTactics.ml
@@ -206,6 +206,11 @@ let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what =
   let uri,metasenv,pbo,pty = proof in
   let (_,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in
   assert (hyps_pat = []); (*CSC: not implemented yet *)
+  let eq_URI =
+   match LibraryObjects.eq_URI () with
+      Some uri -> uri
+    | None -> raise (ProofEngineTypes.Fail (lazy "You need to register the default equality first. Please use the \"default\" command"))
+  in
   let context_len = List.length context in
   let subst,metasenv,u,_,selected_terms_with_context =
    ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph
@@ -269,7 +274,7 @@ let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what =
             ~start:(
               P.cut_tac 
                (C.Appl [
-                 (C.MutInd (LibraryObjects.eq_URI (), 0, [])) ;
+                 (C.MutInd (eq_URI, 0, [])) ;
                  ty_of_with_what ; 
                  what ; 
                  with_what]))