@ombro/is-main

Check if the current module is an entry module for ESM, usually useful in command line scripts.

Install

$ npm install @ombro/is-main

Usage

import { isMain } from '@ombro/is-main'

if (isMain(import.meta)) {
  // ...
}

If you're using CommonJS modules, then judge directly:

if (require.main === module) {
  // ...
}

Example

Suppose we want to create two tasks, clean and build. Before build, we will pass a parameter --clean to determine whether clean needs to be performed first, and the clean task can also be executed separately

# Only clean
node clean.js

# Only build
node build.js
# Clean and build
node build.js --clean

clean.js:

import { isMain } from '@ombro/is-main'

export function clean() {
  // clean...
}

// Executed only when the clean.js is an entry module
if (isMain(import.meta)) {
  clean()
}

build.js:

import { isMain } from '@ombro/is-main'
import { clean } from './clean.js'

export function build() {
  // build...
}

// Executed only when the build.js is an entry module
if (isMain(import.meta)) {
  process.argv.includes('--clean') && clean()
  build()
}

License

MIT