document that numberIsNaN is for IE11

diff --git a/index.js b/index.js
index 8fdb388af6f8d427474c56fca069494f6c2960cb..28347def8e5b09ff3d82287008060c1b28655693 100644 (file)
--- a/index.js
+++ b/index.js
@@ -1744,7 +1744,7 @@ function isInstance (obj, type) {
   return obj instanceof type ||
     (obj != null && obj.constructor != null && obj.constructor.name === type.name)
 }
-
 function numberIsNaN (obj) {
+  // For IE11 support
   return obj !== obj // eslint-disable-line no-self-compare
 }