Defer - API

A defer function defers the execution of a function until the surrounding function returns.

Installation

npm

npm is the default package manager for Node.js, and to where tscommon is published.
Your project is using npm if it has a package-lock.json file in its root folder.

Run the following command in your terminal:

terminal

npm install @tscommon/defer

yarn

yarn is a fast, reliable and secure dependency manager for Node.js.
Your project is using Yarn if it has a yarn.lock file in its root folder.

Run the following command in your terminal:

terminal

yarn add @tscommon/defer

pnpm

pnpm is a fast, disk space efficient package manager for Node.js.
Your project is using pnpm if it has a pnpm-lock.yaml file in its root folder.

Run the following command in your terminal:

terminal

pnpm add @tscommon/defer

Usage

Synchronous

main.ts

import { DeferFunction } from '@tscommon/defer';

// It is important to use the `using` keyword here.
using defer = new DeferFunction();

console.log('start');
defer(() => console.log('a'));
defer(() => console.log('b'));
console.log('end');

// Output:
// start
// end
// b
// a

Asynchronous

main.ts

import { setTimeout } from 'timers/promises';
import { DeferFunction } from '@tscommon/defer';

async function println(message: string): Promise<void> {
  await setTimeout(Math.random() * 1000);
  console.log(message);
}

async function main(): Promise<void> {
  // It is important to use the `using` keyword here.
  await using defer = new DeferFunction();
  console.log('start');
  defer(() => println('a'));
  defer(() => println('b'));
  console.log('end');
}

main();

// Output:
// start
// end
// b
// a