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# Error: $compile:noident
Controller identifier is required.

    Cannot bind to controller without identifier for directive '{0}'.

## Description

When using the `bindToController` feature of AngularJS, a directive is required to have a Controller identifier, which is initialized in scope with the value of the controller instance. This can be supplied using the "controllerAs" property of the directive object, or alternatively by adding " as IDENTIFIER" to the controller name.

For example, the following directives are valid:

    // OKAY, because controller is a string with an identifier component.
    directive("okay", function() {
      return {
        bindToController: true,
        controller: "myCtrl as $ctrl"
        scope: {
          text: "@text"
        }
      };
    });

    // OKAY, because the directive uses the controllerAs property to override
    // the controller identifier.
    directive("okay2", function() {
      return {
        bindToController: true,
        controllerAs: "$ctrl",
        controller: function() {

        },
        scope: {
          text: "@text"
        }
      };
    });

While the following are invalid:

    // BAD, because the controller property is a string with no identifier.
    directive("bad", function() {
      return {
        bindToController: true,
        controller: "noIdentCtrl",
        scope: {
          text: "@text"
        }
      };
    });

    // BAD because the controller is not a string (therefore has no identifier),
    // and there is no controllerAs property.
    directive("bad2", function() {
      return {
        bindToController: true,
        controller: function noControllerAs() {

        },
        scope: {
          text: "@text"
        }
      };
    });