From cdaefe18f6984d0dadd5ea24dbb8dc9f4de36301 Mon Sep 17 00:00:00 2001
From: Putnam3145 <putnam3145@gmail.com>
Date: Sun, 7 Aug 2022 17:32:19 -0700
Subject: [PATCH] needs filterMap

---
 tgui/packages/common/collections.ts | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tgui/packages/common/collections.ts b/tgui/packages/common/collections.ts
index 7abe49ff23..a5ccd7003e 100644
--- a/tgui/packages/common/collections.ts
+++ b/tgui/packages/common/collections.ts
@@ -123,6 +123,26 @@ export const map = iterateeFn => collection => {
   throw new Error(`map() can't iterate on type ${typeof collection}`);
 };
 
+/**
+ * Given a collection, will run each element through an iteratee function.
+ * Will then filter out undefined values.
+ */
+export const filterMap = <T, U>(
+  collection: T[],
+  iterateeFn: (value: T) => U | undefined
+): U[] => {
+  const finalCollection: U[] = [];
+
+  for (const value of collection) {
+    const output = iterateeFn(value);
+    if (output !== undefined) {
+      finalCollection.push(output);
+    }
+  }
+
+  return finalCollection;
+};
+
 const COMPARATOR = (objA, objB) => {
   const criteriaA = objA.criteria;
   const criteriaB = objB.criteria;