From fd1f75e9a311d0c2cdbd6e756ce0644fa2a315eb Mon Sep 17 00:00:00 2001
From: Jonathan Olson <jonathan.olson@colorado.edu>
Date: Wed, 3 Aug 2022 13:39:09 -0600
Subject: [PATCH] Screen-related work for
 https://github.com/phetsims/joist/issues/827

---
 js/{isArray.js => isArray.ts} | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
 rename js/{isArray.js => isArray.ts} (78%)

diff --git a/js/isArray.js b/js/isArray.ts
similarity index 78%
rename from js/isArray.js
rename to js/isArray.ts
index c0657f6..463ad65 100644
--- a/js/isArray.js
+++ b/js/isArray.ts
@@ -7,8 +7,9 @@
  */
 
 import phetCore from './phetCore.js';
+import IntentionalAny from './types/IntentionalAny.js';
 
-function isArray( array ) {
+function isArray( array: IntentionalAny ): array is IntentionalAny[] {
   // yes, this is actually how to do this. see http://stackoverflow.com/questions/4775722/javascript-check-if-object-is-array
   return Object.prototype.toString.call( array ) === '[object Array]';
 }