JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>
<div ng-app="app" ng-controller="mainCtrl">
    <textarea keyup="">{{current_element.value}}</textarea>
    <textarea id="23423" keyup="">{{current_element.value}}</textarea>
    <br>
    <button ng-click="current(0)">first</button>
    <button ng-click="current(1)">second</button>
</div>

JavaScript

angular.module('app', [])
.controller('mainCtrl', function($scope) {
    $scope.elements = [{value: 'first'}, {value: 'second'}];
    $scope.current_element = null;
    
    $scope.current = function(idx) {
        $scope.current_element = $scope.elements[idx];
        console.log('current is', $scope.current_element.value);
    }

    $scope.elements[1].value = 'second modified';
})
.directive('keyup', function() {
    return {
        restrict: 'A',
        link: function(scope, element, attrs) {
            $(element).bind('keyup', function(e) {
                var val = $(this).val();
                scope.$apply(function() {
                    scope.current_element.value = val;
                    console.log(scope.elements);
                });
            });
        }
    }
})