From c0dafb980f5534f878b3b5fe91ed7cdde99a6176 Mon Sep 17 00:00:00 2001
From: Karsten Schmidt <k@postspectacular.com>
Date: Fri, 7 Jun 2019 21:30:51 +0100
Subject: [PATCH] fix(memoize): return type memoize1()

---
 packages/memoize/src/memoize1.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/memoize/src/memoize1.ts b/packages/memoize/src/memoize1.ts
index 06934d6fe0..efa0fd32b6 100644
--- a/packages/memoize/src/memoize1.ts
+++ b/packages/memoize/src/memoize1.ts
@@ -13,10 +13,10 @@ import { Fn1, MapLike } from "./api";
  */
 export function memoize1<A, B>(fn: Fn1<A, B>, cache?: MapLike<A, B>) {
     !cache && (cache = new Map());
-    return (x: A) => {
+    return (x: A): B => {
         let res;
         return cache!.has(x)
-            ? cache!.get(x)
+            ? cache!.get(x)!
             : (cache!.set(x, (res = fn(x))), res);
     };
 }