Update gap/oper.gi

Co-authored-by: James Mitchell <james-d-mitchell@users.noreply.github.com>
DanielPointon · Feb 13, 2024 · afc524f · afc524f
1 parent 6c715e6
commit afc524f
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/gap/oper.gi b/gap/oper.gi
@@ -2026,7 +2026,7 @@ function(D, roots)
   visited := BlistList([1 .. N], []);
 
   for root in roots do
-    if 0 = root or root > N then
+    if not IsPosInt(N) or 0 = root or root > N then
       ErrorNoReturn("an element of the 2nd argument ",
                     "(roots) is not a vertex of the 1st ",
                     "argument (a digraph)");