const randomElement = document.getElementById('someElement');
randomElement.innerHTML = '<p>changing the DOM</p>'

(function(){
    //
    var $posts = $('#posts li');
    var $search = $('#search');
    var cache = [];

    $posts.each(function(){
        cache.push({
            element: this,
            title: this.title.trim().toLowerCase(),
        });
    });

    function filter(){
        var query = this.value;
        console.log("query is "+query);
        cache.forEach(function(post){
            var index = 0;

            if (query) {
                index = post.title.indexOf(query);

            }
            var results = document.getElementsByClassName('search-results');
            results.innerHTML = "<li>"+cache.title+"</li>";
            post.element.style.display = index === -1 ? 'none' : '';
        });
    }

   if ('oninput' in $search[0]){
        $search.on('input', filter);
    } else {
        $search.on('keyup', filter);
    }

}());

var allElements = $("*");

var blogHeaders = $("h2");

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var slug = require('mongoose-slug-generator');

mongoose.plugin(slug);

const pageSchema = new Schema({
    title: { type: String , required: true},
    slug: { type: String, slug: "title" }
});

var Page = mongoose.model('Page', pageSchema);
module.exports = Page;

function copyToClipboard(){

    var codeToBeCopied = document.getElementById('code-snippet').innerText;
    var emptyArea = document.createElement('TEXTAREA');
    emptyArea.innerHTML = codeToBeCopied;
    const parentElement = document.getElementById('post-title');
    parentElement.appendChild(emptyArea);

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

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

    }

const songs[];
const results;

for (var i, i++, i<songs.length){
    if(song[i].artist == "Drake"){
      result.push(songs[i]);
    };

// OR

const songs [];
const result = songs.filter ( song => song.artist == "Drake");

db.students.update(
   { _id: 1 },
   { $push: { scores: 89 } }
)

var allActionButtons = document.getElementsByClassName("action-buttons");

for (var i = 0; i < allActionButtons.length; i++) {

  allActionButtons[i].addEventListener('click', functionToRunWhenClicked, false);

}

var functionToRunWhenClicked = function {
  // Add some stuff here
}

var newForm = document.getElementById('new-form');

if ( newForm.getAttribute('class') === 'make-blue' ) {
        //  Do something
    }  

<form action="/new" method="post">
 
  <input name="title" type="text">
  <input name="description" type="text">
  <button type="submit">Submit Form</button>
 
</form>

<h2 style="text-align:center">Modal Image Gallery</h2>
<div class="row">
  <div class="column">
    <img src="placeholder.png" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="placeholder.png" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="placeholder.png" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="placeholder.png" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
  </div>
</div>
<div id="myModal" class="modal">
  <span class="close cursor" onclick="closeModal()">&times;</span>
  <div class="modal-content">
    <div class="mySlides">
      <div class="numbertext">1 / 4</div>
      <img src="placeholder.png" style="width:100%">
    </div>
    <div class="mySlides">
      <div class="numbertext">2 / 4</div>
      <img src="placeholder.png" style="width:100%">
    </div>
    <div class="mySlides">
      <div class="numbertext">3 / 4</div>
      <img src="placeholder.png" style="width:100%">
    </div>
    <div class="mySlides">
      <div class="numbertext">4 / 4</div>
      <img src="placeholder.png" style="width:100%">
    </div>
    <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
    <a class="next" onclick="plusSlides(1)">&#10095;</a>
    <div class="caption-container">
      <p id="caption"></p>
    </div>
    <div class="column">
      <img class="demo cursor" src="placeholder.png" style="width:100%" onclick="currentSlide(1)" alt="Sample image 1">
    </div>
    <div class="column">
      <img class="demo cursor" src="placeholder.png" style="width:100%" onclick="currentSlide(2)" alt="Sample image 2">
    </div>
    <div class="column">
      <img class="demo cursor" src="placeholder.png" style="width:100%" onclick="currentSlide(3)" alt="Sample image 3">
    </div>
    <div class="column">
      <img class="demo cursor" src="placeholder.png" style="width:100%" onclick="currentSlide(4)" alt="Sample image 4">
    </div>
  </div>
</div>

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

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

<script>

$(document).ready(function(){
    var codeText = $(".codemirror-textarea")[0];
    var editor = CodeMirror.fromTextArea(codeText, {
        lineNumbers : true
    });
});

</script>

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

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

const exampleSchema = new Schema({
    title: { type: String , required: true},
    content: [{type: String}]
});


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

<button id="open-sesame">Open</button>

                <script>
                    var openSesame = document.getElementById('open-sesame');
                    openSesame.addEventListener("click", function(){
                        $('.sidenav').sidenav('open');
                    });
                </script>

<h2 id="lastHeading">Thank you for reading</h2>

<h2 class="redHeading">Welcome</h2>
<p>A passage of text</p>
<h2 class="redHeading">Thank you</h2>

npm install heroku-ssl-redirect