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Wraplet and WrapletApi

What defines a wraplet is the implementation of the Wraplet interface that consists of two properties:

  • The [WrapletSymbol] property having the value true,
  • The wraplet property that implements the WrapletApi interface.

WrapletApi makes it possible to tie together lifecycles of multiple wraplets, allowing complex components to emerge.

interface Wraplet {
  [WrapletSymbol]: true;
  wraplet: WrapletApi;
}
interface WrapletApi {
  [WrapletApiSymbol]: true;

  status: Status;

  destroy(): Promise<void>;

  initialize(): Promise<void>;

  addDestroyListener(callback: DestroyListener): void;
}

WrapletApi's properties are:

status​

interface Status {
  readonly isInitialized: boolean;
  readonly isGettingInitialized: boolean;
  readonly isDestroyed: boolean;
  readonly isGettingDestroyed: boolean;
}

The status property is a read-only object that contains information about the wraplet's lifecycle.

destroy​

destroy is an asynchronous method that's responsible for destroying a wraplet.

initialize​

initialize is an asynchronous method that's responsible for initializing a wraplet.

addDestroyListener​

addDestroyListener is a method that allows you to add a listener to the wraplet that will be executed during wraplet's destruction.

type DestroyListener<W extends Wraplet = Wraplet> = (
  wraplet: W,
) => Promise<void>;

Examples​

A non-dependent wraplet​

In this example we'll create a simple custom class implementing the Wraplet interface without extending any other class.