From 395cfa61089efc4ab3ea1b6c6842521bad31efed Mon Sep 17 00:00:00 2001
From: Aya Morisawa <AyaMorisawa4869@gmail.com>
Date: Thu, 6 Sep 2018 02:16:08 +0900
Subject: Resolve #2625 (#2627)

---
 src/prelude/array.ts | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 src/prelude/array.ts

(limited to 'src/prelude/array.ts')

diff --git a/src/prelude/array.ts b/src/prelude/array.ts
new file mode 100644
index 0000000000..e944030a7f
--- /dev/null
+++ b/src/prelude/array.ts
@@ -0,0 +1,7 @@
+export function countIf<T>(f: (x: T) => boolean, xs: T[]): number {
+	return xs.filter(f).length;
+}
+
+export function count<T>(x: T, xs: T[]): number {
+	return countIf(y => x === y, xs);
+}
-- 
cgit v1.2.3-freya