PHP-like `empty` Function in Vanilla JS

empty.js

/**
 * Like PHP's {@link https://www.php.net/manual/en/function.empty.php `empty`} function in vanilla JavaScript.
 *
 * @author Davey Jacobson <daveyjake21 [at] geemail [dot] com>
 * @since 1.0.0
 * @since 1.0.1 Gist made public.
 *
 * @param {array|bool|number|object|string} value          The value to check.
 * @param {bool}                            [strict=false] Enable strict checking. Accepts true, false.
 *
 * @return {bool} False if `value` contains anything. True if not. Default false.
 */
function empty( $value, $strict ) {
    // Strict checking is disabled by default.
    $strict = $strict || false;

    /**
     * Values and items that are inherently empty.
     *
     * @since 1.0.0
     * @since 1.0.1 Added 'null' and 'undefined'.
     * @since 1.0.2 Added `NaN` and 'NaN'.
     *
     * @type array
     */
    var emptyValues = [ 0, '0', false, 'false', '', [], {}, NaN, 'NaN', null, 'null', undefined, 'undefined' ];

    // Result of testing `$value`.
    var result;

    // Checking the `$value`.
    if ( ! $strict ) {
        // Check if `$value` is found inside the `emptyValues` array.
        result = emptyValues.indexOf( $value );

        // If the `result` is greater than -1, `$value` is one of the `emptyValues` elements.
        return result > -1 ? true : false;
    } else {
        /**
         * Strictly check the value to confirm it's not inherently empty.
         *
         * @since 1.0.0
         *
         * @link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce
         */
        result = emptyValues.reduce( function( sum, current ) {
            // Check if `current` explicitly matches the `value`.
            var i = ( current === $value ? 1 : 0 );

            return sum + i;
        });

        // If `result` is greater than 0, we know it's inherently empty.
        return result > 0 ? true : false;
    }

    // Just in case something goes wrong and we end up here.
    return false;
}