angular2
Version:
Angular 2 - a web framework for modern web apps
45 lines • 4.73 kB
JavaScript
;"use strict";
var lang_1 = require('angular2/src/facade/lang');
/**
* Allows to refer to references which are not yet defined.
*
* For instance, `forwardRef` is used when the `token` which we need to refer to for the purposes of
* DI is declared,
* but not yet defined. It is also used when the `token` which we use when creating a query is not
* yet defined.
*
* ### Example
* {@example core/di/ts/forward_ref/forward_ref.ts region='forward_ref'}
*/
function forwardRef(forwardRefFn) {
forwardRefFn.__forward_ref__ = forwardRef;
forwardRefFn.toString = function () { return lang_1.stringify(this()); };
return forwardRefFn;
}
exports.forwardRef = forwardRef;
/**
* Lazily retrieves the reference value from a forwardRef.
*
* Acts as the identity function when given a non-forward-ref value.
*
* ### Example ([live demo](http://plnkr.co/edit/GU72mJrk1fiodChcmiDR?p=preview))
*
* ```typescript
* var ref = forwardRef(() => "refValue");
* expect(resolveForwardRef(ref)).toEqual("refValue");
* expect(resolveForwardRef("regularValue")).toEqual("regularValue");
* ```
*
* See: {@link forwardRef}
*/
function resolveForwardRef(type) {
if (lang_1.isFunction(type) && type.hasOwnProperty('__forward_ref__') &&
type.__forward_ref__ === forwardRef) {
return type();
}
else {
return type;
}
}
exports.resolveForwardRef = resolveForwardRef;
//# sourceMappingURL=data:application/json;base64,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