All files / fuse-ui-shared/decorators lazy.ts

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
 
 
 
 
 
 
 
 
 
1x
1x
1x
1x
1x
1x
 
1x
 
1x
 
 
 
1x
 
1x
 
 
1x
 
 
 
/**
 * lazy decorator
 *
 * @lazy()
 * get prop() : T {
 *   // code to create the return type and then once
 *   // created it is cached for future invocations
 * }
 */
export function lazy() {
  return function (target: any, propertyKey: string, descriptor: PropertyDescriptor) {
    let { configurable, enumerable, writable } = descriptor;
    let innerGet = descriptor.get;
    Eif (typeof innerGet === 'function') {
      let getter = function () {
        // tslint:disable-next-line:no-invalid-this
        let val = innerGet.apply(this);
        // tslint:disable-next-line:no-invalid-this
        Object.defineProperty(this, propertyKey, {
          configurable, enumerable, writable, value: val
        });
 
        return val;
      };
      descriptor.get = getter;
    }
 
    return descriptor;
  };
}