array: fix Array::swap_at

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/lib/standard/collection/array.nit b/lib/standard/collection/array.nit
index 23fcf5f..e010470 100644 (file)
--- a/lib/standard/collection/array.nit
+++ b/lib/standard/collection/array.nit
@@ -245,7 +245,7 @@ abstract class AbstractArray[E]
        fun swap_at(a: Int,b: Int)
        do
            var e = self[a]
-           self[a] = b
+           self[a] = self[b]
            self[b] = e
        end
 end