Amélioration hashCode

src/migl/util/ConsListImpl.java

@@ -91,8 +91,11 @@ public class ConsListImpl<E> extends Cons<E, ConsList<E>> implements ConsList<E>
 
 	@Override
 	public int hashCode() {
-		int result = super.hashCode();
-		return result + size * this.left().hashCode();
+		final int prime = 31;
+        int result = 1;
+        result = prime * result + ((this.left() == null) ? 0 : this.left().hashCode());
+        result = prime * result + ((this.right() == null) ? 0 : this.right().hashCode());
+        return prime * result + this.size;
 	}
 
 	@Override