counter: fix add all behavior

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>

diff --git a/lib/counter.nit b/lib/counter.nit
index ceb9896..e539bc5 100644 (file)
--- a/lib/counter.nit
+++ b/lib/counter.nit
@@ -80,6 +80,12 @@ class Counter[E]
                map.clear
        end
 
+       redef fun add_all(other) do
+               for k, v in other do
+                       self[k] += v
+               end
+       end
+
        # Count one more occurrence of `e`
        fun inc(e: E)
        do