react app

react-app/node_modules/core-js/modules/es6.function.has-instance.js

@@ -0,0 +1,13 @@
+'use strict';
+var $             = require('./$')
+  , isObject      = require('./$.is-object')
+  , HAS_INSTANCE  = require('./$.wks')('hasInstance')
+  , FunctionProto = Function.prototype;
+// 19.2.3.6 Function.prototype[@@hasInstance](V)
+if(!(HAS_INSTANCE in FunctionProto))$.setDesc(FunctionProto, HAS_INSTANCE, {value: function(O){
+  if(typeof this != 'function' || !isObject(O))return false;
+  if(!isObject(this.prototype))return O instanceof this;
+  // for environment w/o native `@@hasInstance` logic enough `instanceof`, but add this:
+  while(O = $.getProto(O))if(this.prototype === O)return true;
+  return false;
+}});