is-installed

Checks that given package is installed locally or globally. Useful for robust resolving when you want some package - it will check first if it exists locally, then if it exists globally

You might also be interested in get-installed-path.

Table of Contents

• Install
• Usage
• API
  • isInstalled
  • .sync
• Related
• Contributing
• Building docs
• Running tests
• Author
• License

(TOC generated by verb using markdown-toc)

Install

Install with npm

$ npm install is-installed --save

or install using yarn

$ yarn add is-installed

Usage

For more use-cases see the tests

const isInstalled = require('is-installed')

API

isInstalled

Check if given name package is installed locally, then checks if it exists globally, using detect-installed and so global-modules (which in turn rely on global-prefix). Windows bugs comes from global-prefix.

Params

• name {String}: package name
• returns {Promise}: resolved promise with boolean value

Example

const isInstalled = require('is-installed')

isInstalled('npm').then((exists) => {
  console.log(exists) // => true
})

// installed locally for this package
isInstalled('detect-installed').then((exists) => {
  console.log(exists) // => true
})

isInstalled('foo-bar-baz-qux').then((exists) => {
  console.log(exists) // => false
})

.sync

Synchronously check if package name is installed.

Params

• name {String}: package name
• returns {Boolean}: always boolean true or false

Example

const isInstalled = require('is-installed')

const npmExists = isInstalled.sync('npm')
console.log(npmExists) // => true

const notExists = isInstalled.sync('foo-abra-fsddsfsd-fsdf')
console.log(notExists) // => false

Related

• always-done: Handle completion and errors with elegance! Support for streams, callbacks, promises, child processes, async/await and sync functions. A drop-in replacement… more | homepage
• detect-installed: Checks that given package is installed globally or locally. | homepage
• get-installed-path: Get locally or globally installation path of given package name | homepage
• global-modules: The directory used by npm for globally installed npm modules. | homepage
• global-paths: Returns an array of unique "global" directories based on the user's platform and environment. The resulting paths can be used… more | [homepage](https://github.com/jonschlinkert/global-paths "Returns an array of unique "global" directories based on the user's platform and environment. The resulting paths can be used for doing lookups for generators or other globally installed npm packages. Node.js / JavaScript.")
• global-prefix: Get the npm global path prefix. | homepage
• minibase: Minimalist alternative for Base. Build complex APIs with small units called plugins. Works well with most of the already existing… more | homepage
• try-catch-core: Low-level package to handle completion and errors of sync or asynchronous functions, using once and dezalgo libs. Useful for and… more | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Please read the contributing guidelines for advice on opening issues, pull requests, and coding standards.
If you need some help and can spent some cash, feel free to contact me at CodeMentor.io too.

In short: If you want to contribute to that project, please follow these things

1. Please DO NOT edit README.md, CHANGELOG.md and .verb.md files. See "Building docs" section.
2. Ensure anything is okey by installing the dependencies and run the tests. See "Running tests" section.
3. Always use npm run commit to commit changes instead of git commit, because it is interactive and user-friendly. It uses commitizen behind the scenes, which follows Conventional Changelog idealogy.
4. Do NOT bump the version in package.json. For that we use npm run release, which is standard-version and follows Conventional Changelog idealogy.

Thanks a lot! :)

Building docs

Documentation and that readme is generated using verb-generate-readme, which is a verb generator, so you need to install both of them and then run verb command like that

$ npm install verbose/verb#dev verb-generate-readme --global && verb

Please don't edit the README directly. Any changes to the readme must be made in .verb.md.

Running tests

Clone repository and run the following in that cloned directory

$ npm install && npm test

Author

Charlike Mike Reagent

• github/tunnckoCore
• twitter/tunnckoCore
• codementor/tunnckoCore

License

Copyright © 2016, Charlike Mike Reagent. Released under the MIT license.

This file was generated by verb-generate-readme, v0.2.0, on December 11, 2016.
Project scaffolded using charlike cli.