From 1662da4e75ca41c374707addcd4a2a67357c8b19 Mon Sep 17 00:00:00 2001
From: Glen Whitney <gwhitney@post.harvard.edu>
Date: Wed, 25 Oct 2017 16:40:56 +0200
Subject: [PATCH] try to localize strange error

---
 gap/bytable.gi | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/gap/bytable.gi b/gap/bytable.gi
index 0e1b438..976424e 100644
--- a/gap/bytable.gi
+++ b/gap/bytable.gi
@@ -406,15 +406,16 @@ InstallOtherMethod(DirectProductOp,
   "for a list and non-quasigroup magma built form multiplication table",
   [IsList, IsMagma and IsBuiltFromMultiplicationTable],
   function (list, first)
-    local item, i, jof, bigtable;
+    local n, item, i, jof, bigtable;
+    n := Length(list);
     # Simple checks
-    if IsEmpty(list) then
+    if n = 0 then
       Error("Usage: Cannot take DirectProduct of zero items.");
-    elif Length(list) = 1 then
+    elif n = 1 then
       return list[1];
     fi;
     # See if we can handle all objects
-    for i in [2..Length(list)] do
+    for i in [2..n] do
       if not HasMultiplicationTable(list(i)) then
         return DirectProductOp(Permuted(list, (1,i)), list[i]);
       fi;