Map[@@toStringTag] 的初始值是"Map".

Map.prototype[@@toStringTag] 属性的属性特性：
writable false
enumerable false
configurable true

语法

Map[Symbol.toStringTag]

示例

Object.prototype.toString.call(new Map()) // "[object Map]"

规范

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
Map.prototype[@@toStringTag]		 Standard Initial definition.
ECMAScript Latest Draft (ECMA-262)
Map.prototype[@@toStringTag]		 Draft  

浏览器兼容

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Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 44.0 未实现 未实现 未实现 未实现
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support 未实现 44.0 未实现 未实现 未实现 未实现 44.0