Remove unused variable, remember to capitalise variables

src/geef_commit.erl

@@ -8,7 +8,7 @@ tree_id(#object{type=commit,handle=Handle}) ->
     Oid = geef:commit_tree_id(Handle),
     #oid{oid=Oid}.
 
-tree(Obj = #object{type=commit,handle=Handle}) ->
+tree(#object{type=commit,handle=Handle}) ->
     case geef:commit_tree(Handle) of
 	{ok, Type, Handle} ->
 	    {ok, #object{type=Type, handle=Handle}};