AngularJS 1.3.x

var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {
  $scope.name = 'World';
  
  $scope.document = {
    content : '1233_test.txt'
  }
});

<!DOCTYPE html>
<html ng-app="plunker">

<head>
  <meta charset="utf-8" />
  <title>AngularJS Plunker</title>
  <script>
    document.write('<base href="' + document.location + '" />');
  </script>
  <link rel="stylesheet" href="style.css" />
  <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.14/angular.js" data-semver="1.3.14"></script>
  <script src="app.js"></script>
</head>

<body ng-controller="MainCtrl">
  <p>Hello {{name}}!</p>
  <a ng-click="mpla()" ng-bind="document.content.replace(/\d+\_/,'')"></a>
</body>

</html>

/* Put your css in here */