From a1e155d708a4b36bafd6ab2092b046f999687974 Mon Sep 17 00:00:00 2001
From: "James D. Mitchell" <jdm3@st-andrews.ac.uk>
Date: Sun, 25 Jun 2023 10:14:19 +0200
Subject: [PATCH] congsemigraph: add \= method

---
 gap/congruences/congsemigraph.gi | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/gap/congruences/congsemigraph.gi b/gap/congruences/congsemigraph.gi
index ab9199ffd..458d21410 100644
--- a/gap/congruences/congsemigraph.gi
+++ b/gap/congruences/congsemigraph.gi
@@ -272,6 +272,12 @@ function(cong1, cong2)
   return IsSubset(Union(cong2!.H, cong2!.W), Union(cong1!.H, cong1!.W));
 end);
 
+InstallMethod(\=, "for two congruences by Wang pair",
+[IsCongruenceByWangPair, IsCongruenceByWangPair],
+function(cong1, cong2)
+  return cong1!.H = cong2!.H and cong1!.W = cong2!.W;
+end);
+
 InstallMethod(CayleyDigraphOfCongruences,
 "for a graph inverse semigroup",
 [IsGraphInverseSemigroup],