From: Jean Privat <jean@pryen.org>
Date: Fri, 19 Feb 2016 15:34:15 +0000 (-0500)
Subject: lib/core/collection: improve the default `has_all` for basic cases
X-Git-Url: http://nitlanguage.org

lib/core/collection: improve the default `has_all` for basic cases

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

diff --git a/lib/core/collection/abstract_collection.nit b/lib/core/collection/abstract_collection.nit
index 5f9af05..e17ecfa 100644
--- a/lib/core/collection/abstract_collection.nit
+++ b/lib/core/collection/abstract_collection.nit
@@ -149,6 +149,12 @@ interface Collection[E]
 	# It is memory-efficient but relies on `has` so may be CPU-inefficient for some kind of collections.
 	fun has_all(other: Collection[nullable Object]): Bool
 	do
+		if is_same_instance(other) then return true
+		var ol = other.length
+		var  l = length
+		if ol == 0 then return true
+		if l == 0 then return false
+		if ol == 1 then return has(other.first)
 		for x in other do if not has(x) then return false
 		return true
 	end