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

'use strict';

/** @const */
var $Map = typeof Map === 'function' && Map.prototype ? Map : null;
var $Set = typeof Set === 'function' && Set.prototype ? Set : null;

var exported;

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

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

/** @type {import('.')} */
module.exports = exported || function isMap(x) {
        if (!x || typeof x !== 'object') {
                return false;
        }
        try {
                $mapHas.call(x);
                if ($setHas) {
                        try {
                                $setHas.call(x);
                        } catch (e) {
                                return true;
                        }
                }
                // @ts-expect-error TS can't figure out that $Map is always truthy here
                return x instanceof $Map; // core-js workaround, pre-v2.5.0
        } catch (e) {}
        return false;
};