async template loading

1.js

Backbone.View.extend({
  template: 'my-view-template',

  render: function(){
    var that = this;
    $.get("/templates/" + this.template + ".html", function(template){
      var html = $(template).tmpl();
      that.$el.html(html);
    });
    return this;
  }

});

2.js

TemplateManager = {
  templates: {},

  get: function(id, callback){
    var template = this.templates[id];

    if (template) {
      callback(template);

    } else {

      var that = this;
      $.get("/templates/" + id + ".html", function(template)){
        var $tmpl = $(template);
        that.templates[id] = $tmpl;
        callback($tmpl);
      }

    }

  }

}

3.js

Backbone.View.extend({
  template: 'my-view-template',

  render: function(){
    var that = this;
    TemplateManager.get(this.template, function(template){
      var html = $(template).tmpl();
      that.$el.html(html);
    });
    return this;
  }

});

5.js

(function(){
  var promises = {};

  // Cache the returned deferred/promise by the id of the template
  // so that we can prevent multiple requests for the same template
  // from making the ajax call.
  //
  // This code is only safe to run synchronously. There exists a
  // race condition in this function, when run asynchronously,
  // which would nullify the benefit under certain circumstances.
  var loadTemplateAsync = function(tmpId){
    var promise = promises[tmpId] || $.get("/templates/" + tmpId + ".html");
    promises[tmpId] = promise;
    return promise;
  }

  // Use jQuery to asynchronously load the template. 
  Backbone.Marionette.TemplateManager.loadTemplate = function(templateId, callback){
    var tmpId = templateId.replace("#", "");
    var promise = loadTemplateAsync(tmpId);
    promise.done(function(template){
      callback.call(this, $(template));
    });
  }
})();

Goood.
You should add it to the Backbone.Marionette proyect.

Please

(Sorry about my english I'm spanish)