X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_paramodulation%2Fterms.ml;h=3947107eab8bfeea1ba1866f49b60fd9e3328e68;hb=8b1a49bbee9eea86eb74c040defe701370ca5893;hp=9a225fd27b2807f3a3ea37d57276eb93332e384a;hpb=016f069da6221053873b4d505716ef1bd80f08b6;p=helm.git

diff --git a/helm/software/components/ng_paramodulation/terms.ml b/helm/software/components/ng_paramodulation/terms.ml
index 9a225fd27..3947107ea 100644
--- a/helm/software/components/ng_paramodulation/terms.ml
+++ b/helm/software/components/ng_paramodulation/terms.ml
@@ -18,7 +18,7 @@ type 'a foterm =
 
 type 'a substitution = (int * 'a foterm) list
 
-type comparison = Lt | Eq | Gt | Incomparable
+type comparison = Lt | Eq | Gt | Incomparable | Invertible
 
 type rule = Superposition | Demodulation
 type direction = Left2Right | Right2Left | Nodir