This library is inspired by functional programming - Clojure

The minimum and most straightforward way to check if command exists and where the executable is, without spawning child_process.

Check if artifact exists in remote maven repository

Joining Tables in SQL

mongoose validation to ensure referenced object id exists

🪐 The missing fs.promises.exists(). Also supports case-sensitive/insensitive file paths.

Node module to check if a command-line command exists.

DEPRECATED REPO!! New place at https://github.com/tunnckocore/opensource! Next release soon will be published! Return positive value if any of passed values exists in array, or optionally an index.

Returns true if a npm package exists in global node_modules.

Elaborated examples concerning functional concepts e.g. gadt, eadt, church encodings

Laravel validation rule to check if a custom route key exists.

🧩 Pattern matching objects

Check if a name exists on npm registry

Returns existence of key or value in an object

[OBSOLETE] Checks if an e-mail address exists or not

Check if the binary exists on system

Solves routine array actions: get value by key if exists or default; set key if not exists. PHP 5, 7

👐 Extended open command with default dir set to current

Check if the node module has exists

Utility function to check if a file exists and return a Promise