source: imaps-frontend/node_modules/is-weakmap/index.js

'use strict';

var $WeakMap = typeof WeakMap === 'function' && WeakMap.prototype ? WeakMap : null;
var $WeakSet = typeof WeakSet === 'function' && WeakSet.prototype ? WeakSet : null;

var exported;

if (!$WeakMap) {
        /** @type {import('.')} */
        // eslint-disable-next-line no-unused-vars
        exported = function isWeakMap(x) {
                // `WeakMap` is not present in this environment.
                return false;
        };
}

var $mapHas = $WeakMap ? $WeakMap.prototype.has : null;
var $setHas = $WeakSet ? $WeakSet.prototype.has : null;
if (!exported && !$mapHas) {
        /** @type {import('.')} */
        // eslint-disable-next-line no-unused-vars
        exported = function isWeakMap(x) {
                // `WeakMap` does not have a `has` method
                return false;
        };
}

/** @type {import('.')} */
module.exports = exported || function isWeakMap(x) {
        if (!x || typeof x !== 'object') {
                return false;
        }
        try {
                $mapHas.call(x, $mapHas);
                if ($setHas) {
                        try {
                                $setHas.call(x, $setHas);
                        } catch (e) {
                                return true;
                        }
                }
                // @ts-expect-error TS can't figure out that $WeakMap is always truthy here
                return x instanceof $WeakMap; // core-js workaround, pre-v3
        } catch (e) {}
        return false;
};