init: only define GRAPE variables when undefined

digraphs · Feb 17, 2021 · e097454 · e097454
1 parent 0fecc53
commit e097454
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/init.g b/init.g
@@ -27,9 +27,14 @@ fi;
 BindGlobal("DIGRAPHS_IsGrapeLoaded",
            IsPackageMarkedForLoading("grape", "4.8.1"));
 
-if not DIGRAPHS_IsGrapeLoaded then
+# To avoid warnings when GRAPE is not loaded
+if not IsBound(IsGraph) then
   IsGraph := ReturnFalse;
+fi;
+if not IsBound(Vertices) then
   Vertices := IdFunc;
+fi;
+if not IsBound(Adjacency) then
   Adjacency := IdFunc;
 fi;