如何將標籤的內容綁定到指令的作用域？

Question

說我有一個像這樣的指令：

<my-directive>This is my entry!</my-directive> 

我怎樣才能綁定元素的內容爲我指示的範圍是什麼？

myApp.directive('myDirective', function() { 
    return { 
     scope : { 
      entry : "" //what goes here to bind "This is my entry" to scope.entry? 
     }, 
     restrict: "E", 
     template: "<textarea>{{entry}}</textarea>" 
     link: function (scope, elm, attr) { 
     } 
    }; 
});