Aakash appsparkler

Javascript Diary

Callbacks are a great tool to achieve SRP. For ex. the following function is responsbile for submitting forms and nothing else.

// SRP
const submitForm = ({apiUrl, payload, onSuccess, onFailure}) => {
  fetch(apiUrl, payload)
    .then((res) => {

FP looks at things as "What to do?" rather than "How to do it?"

  // imperative way of doing things
  const findMean = (...numbers) => {
    let x = 0;
    numbers.forEach((number) => {
      x += number;

486 ;486

2 numbers


	var filters = ""
	$('img').toArray().forEach(iterateImageElements.bind(this));
	console.log(filters)

	function iterateImageElements(){
	var _this = arguments[0];
	filters += getImagePaths.apply(_this, arguments) + "\n";
	}


	var fileName = 'test-450.json';
	var fileData;
	var savedFileEntry = {};

	promise_getPersistentDirectoryEntry()
	.then(promise_fileEntry.bind(null, fileName, { create:false }))
	.then(save_fileEntry)
	.then(promise_file)
	.then(promise_fileContent)

	// a sample array of items.
	const values = [
	'item1',
	'item2'
	]

	// checkValue(item) is an async that returns true or false.
	const promises = values.map(async(item) => checkValue(item).catch(err => err))
	const results = await Promise.all(results)
	console.log(results); // ['true', 'false'];

	const getIsDisabled = ({fromDate, toDate, selectedKey) => {
	let isDisabled = true; // set the initial value to true
	if(selectedKey === 'valueA') {
	isDisabled = false;
	} else if(selectedKey === 'valueB') {
	if(fromDate) {
	const isfromDateValid = moment(fromDate).isValid();
	const isfromDateGreaterThanOrEqualToToday = moment().diff(fromDate) <= 0;
	if(isfromDateValid && isfromDateGreaterThanOrEqualToToday) {
	isDisabled = false