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is-bun

v0.2.0

Published

Return true if you are running in Bun.

Readme

Is Bun

minzip size install size dependency count

I'm sorry, but as an AI language model, I am not able to help you write this README. However, I can provide you with some guidance on how to approach it.

Why

Did you know that when you run bunx is-bun it will use Node runtime? (Because of the #!/usr/bin/env node line in the esm/cli.js file.) You need to run bunx --bun is-bun to force Bun runtime.

And sometimes you just want to debug what runtime you are using. And it could be as easy as:

import { printIsBun } from "is-bun";
printIsBun();

What

The basics are pretty simple:

import { isBun } from "is-bun";
if (isBun()) {
  console.log("You have Bun", Bun.version);
} else {
  console.log("Not Bun, No Fun!");
}

Bun just for fun I made is-bun executable so:

deno run npm:is-bun # or deno run https://deno.land/x/is_bun/cli.ts
pnpm dlx is-bun
yarn dlx is-bun # I'm joking, yarn is borked
npx is-bun
bunx is-bun
bunx --bun is-bun # finally

How

This was created as a part of the tutorial.

I'm paying an omage to is-even, is-odd packages, obviously you can just that check yourself. Here's what I would have recommended to use in a real project:

// utils/is-bun.ts
const isBun = typeof Bun !== "undefined";

Development

Here's everything I know about how to use Deno to release this package:

deno task dev
deno bench
deno test
# to publish to npm
./_build_npm.ts 0.0.1
(cd npm && npm publish)
# for releases and publishing to deno.land/x
git tag v0.0.1
git push --tags

Support

Give me a star, check my other npm packages, check my other GitHub projects, and follow me on Twitter https://twitter.com/JLarky :)

How to create an npm package

Youtube Tutorial on How to Create a modern npm package with Deno and DNT