is-map Version Badge

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Is this value a JS Map? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Example

```js var isMap = require('is-map'); assert(!isMap(function () {})); assert(!isMap(null)); assert(!isMap(function* () { yield 42; return Infinity; }); assert(!isMap(Symbol('foo'))); assert(!isMap(1n)); assert(!isMap(Object(1n)));

assert(!isMap(new Set())); assert(!isMap(new WeakSet())); assert(!isMap(new WeakMap()));

assert(isMap(new Map()));

class MyMap extends Map {} assert(isMap(new MyMap())); ```

Tests

Simply clone the repo, npm install, and run npm test