From b2231c44e61f527171b795de59ae892bd31f9722 Mon Sep 17 00:00:00 2001
From: kalmar <kalmar@amu.edu.pl>
Date: Mon, 5 Jun 2017 21:37:11 +0200
Subject: [PATCH] coercion to GroupRing via specified function on underlying
 groups

---
 src/GroupRings.jl | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/GroupRings.jl b/src/GroupRings.jl
index 31bbff1..c8ffbc2 100644
--- a/src/GroupRings.jl
+++ b/src/GroupRings.jl
@@ -136,6 +136,14 @@ function (RG::GroupRing)(X::GroupRingElem)
    return RG(X.coeffs)
 end
 
+function (RG::GroupRing)(X::GroupRingElem, emb::Function)
+    result = RG(eltype(X.coeffs))
+    for g in parent(X).basis
+        result[emb(g)] = X[g]
+    end
+    return result
+end
+
 ###############################################################################
 #
 #   Basic manipulation