flash and hide jquery addition

flash.js

// Extend jquery with flashing for elements
$.fn.flash = function(duration, iterations, hideAfter) {
    duration = duration || 1000; // Default to 1 second
    iterations = iterations || 1; // Default to 1 iteration
    const iterationDuration = Math.floor(duration / iterations);

    for (let i = 0; i < iterations; i++) {
        this.fadeOut(iterationDuration).fadeIn(iterationDuration);
    }

    if (hideAfter) {
      let hide = () => this.hide()
      hide = hide.bind(this)
      setTimeout(hide, hideAfter + iterations * duration)
    }

    // allow method chaining
    return this;
}

module.exports = $.fn.flash