JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.6/angular.min.js"></script>

    <script type='text/javascript'>


            var app = angular.module('app', []);
            app.controller('ctrl', function ($scope) {
                $scope.showValues = function () {
                    alert('oldValue = ' + $scope.oldValue);
                    alert('newValue = ' + $scope.a.b);
                }
            });

    </script>

    <div ng-app="app" ng-controller="ctrl">
        <input type="text" id="exampleab" ng-model="a.b" ng-init="oldValue = ''" ng-focus="oldValue = a.b" ng-blur="showValues()" />
    </div>