javascript - What's the difference between using "let" and "var"? - Stack Overflow

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Thu Jul 29 2021 12:06:01 GMT+0000 (Coordinated Universal Time)

Saved by @joannpav #javascript #interview

function run() {
  var foo = "Foo";
  let bar = "Bar";

  console.log(foo, bar); // Foo Bar

  {
    var moo = "Mooo"
    let baz = "Bazz";
    console.log(moo, baz); // Mooo Bazz
  }

  console.log(moo); // Mooo
  console.log(baz); // ReferenceError
}

run();

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Good question to give to interview candidate

https://stackoverflow.com/questions/762011/whats-the-difference-between-using-let-and-var

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Javascript

@joannpav

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How to Save HTML Form Data in JSON - Express

<form action="/new" method="post">
 
  <input name="title" type="text">
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<body>
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</body>

<script>

$(document).ready(function(){
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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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    content: [{type: String}]
});


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

> More steps

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<html>

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

<script>

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Full Stack Developer

function full_stack_developer() {
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}

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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:
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    emptyArea.select();
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    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() {
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jQuery.post() - AJAX for post requests

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  type: "POST",
  url: url,
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  success: success,
  dataType: dataType
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