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node_modules/core-js/internals/classof.js

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+'use strict';
+var TO_STRING_TAG_SUPPORT = require('../internals/to-string-tag-support');
+var isCallable = require('../internals/is-callable');
+var classofRaw = require('../internals/classof-raw');
+var wellKnownSymbol = require('../internals/well-known-symbol');
+
+var TO_STRING_TAG = wellKnownSymbol('toStringTag');
+var $Object = Object;
+
+// ES3 wrong here
+var CORRECT_ARGUMENTS = classofRaw(function () { return arguments; }()) == 'Arguments';
+
+// fallback for IE11 Script Access Denied error
+var tryGet = function (it, key) {
+  try {
+    return it[key];
+  } catch (error) { /* empty */ }
+};
+
+// getting tag from ES6+ `Object.prototype.toString`
+module.exports = TO_STRING_TAG_SUPPORT ? classofRaw : function (it) {
+  var O, tag, result;
+  return it === undefined ? 'Undefined' : it === null ? 'Null'
+    // @@toStringTag case
+    : typeof (tag = tryGet(O = $Object(it), TO_STRING_TAG)) == 'string' ? tag
+    // builtinTag case
+    : CORRECT_ARGUMENTS ? classofRaw(O)
+    // ES3 arguments fallback
+    : (result = classofRaw(O)) == 'Object' && isCallable(O.callee) ? 'Arguments' : result;
+};