Promises

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Thu Apr 08 2021 08:03:40 GMT+0000 (UTC)

// Promise takes two functions as arguments
// You call resolve when the function succeeds
const okPromise = new Promise(function(resolve, reject) {
    resolve({result: ['1','2']}) // you can pass data to the callback
  });
  
   // You call reject when it fails
   const koPromise = new Promise(function(resolve, reject) {
    reject(new Error('not found')) // you can pass data to the callback
  });
  
  // The promise rejects if you throw an error
  const throwedPromise = new Promise(function(resolve, reject) {
    throw new Error('not found') // you can pass data to the callback
  });
  
  // Promise can be created using "async" keyword
  // It resolves with returned value
  // Rejects if an error is thrown
  const asyncPromise = async function() {
    return true;
  }
  
  // You can call other promises by using .then for getting the result
  okPromise.then(function(result) {
    console.info(result) // {result: ['1','2']}
  }).catch((err) => console.info(err)) // nothing displayed
  // Use .catch for catch the error of a promise
  koPromise.then(function(result) {
    console.info(result) // nothing displayed
  }).catch((err) => console.info(err)) // Error: not found

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@Pepe

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Replace Textarea with Codemirror editor

<link rel="stylesheet" type="text/css" href="plugin/codemirror/lib/codemirror.css">

<body>
	<textarea class="codemirror-textarea"></textarea>
</body>

<script>

$(document).ready(function(){
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    var editor = CodeMirror.fromTextArea(codeText, {
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});

</script>

<script type="text/javascript" src="plugin/codemirror/lib/codemirror.js"></script>

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npm install heroku-ssl-redirect

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var mongoose = require('mongoose');
var Schema = mongoose.Schema;

const exampleSchema = new Schema({
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});


var Example = mongoose.model('Example', exampleSchema);
module.exports = Example;

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<html>

<input id="contact" name="address">

<script>

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</script>

</html>

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function full_stack_developer() {
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var url = "http://scratch99.com/web-development/javascript/";
var urlParts = url.replace('http://','').replace('https://','').split(/[/?#]/);
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Required Parameters for Functions in JavaScript

 const isRequired = () => { throw new Error('param is required'); };

const hello = (name = isRequired()) => { console.log(`hello ${name}`) };

// These will throw errors
hello();
hello(undefined);

// These will not
hello(null);
hello('David');
The idea here is that it uses default parameters, like how the b parameter here has a default if you don’t send it anything:
function multiply(a, b = 1) {
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}

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const object1 = {
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for (let [key, value] of Object.entries(object1)) {
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}

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    emptyArea.select();
    document.execCommand('copy');

    parentElement.removeChild(emptyArea);
    M.toast({html: 'Code copied to clipboard'})

    }

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How to store fetch response in javascript variable - Stack Overflow

async function fun() {
  return fetch('https://jsonplaceholder.typicode.com/todos/1').then(res => res.json());
}

const data  = await fun();

#javascript #jquery

jQuery.post() - AJAX for post requests

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  type: "POST",
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

Promises

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