JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0-rc.2/angular.min.js"></script>
<div ng-app ng-controller="myCtrl">
    <button ng-click="changeIt()">Change It</button>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}} again!</div>
    <div class="{{variableInScope}}">We print {{variableInScope}}...

JavaScript

function myCtrl($scope) {
    $scope.variableInScope = "Hello World!";
    var count = 0
    $scope.$watch(function() {
        // this function runs every time watch is called in this scope.
        count++;
        console.log(count);
        return true;
    },function(){
        
    })
    $scope.changeIt = function(){
        $scope.variableInScope = "Something New";
    }
}