Small and fast library to set default values.

Usage no npm install needed!

<script type="module">
  import deffy from '';




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Small and fast library to set default values.

:cloud: Installation

# Using npm
npm install --save deffy

# Using yarn
yarn add deffy

:clipboard: Example

// Dependencies
var Deffy = require("deffy");

console.log(Deffy(undefined, "Hello World"));
// => "Hello World"

console.log(Deffy("Hello World", 42));
// => 42

console.log(Deffy("Hello", "World"));
// => "World"

console.log(Deffy("", "World", true));
// => "World"

console.log(Deffy("", "World"));
// => ""

console.log(Deffy("foo", function (input) {
    return input === "foo" ? "bar" : "foo";
// => "bar"

:question: Get Help

There are few ways to get help:

  1. Please post questions on Stack Overflow. You can open issues with questions, as long you add a link to your Stack Overflow question.
  2. For bug reports and feature requests, open issues. :bug:
  3. For direct and quick help, you can use Codementor. :rocket:

:memo: Documentation

Deffy(input, def, options)

Computes a final value by providing the input and default values.


  • Anything input: The input value.

  • Anything|Function def: The default value or a function getting the input value as first argument.

  • Object|Boolean options: The empty value or an object containing the following fields:

  • empty (Boolean): Handles the input value as empty field (input || default). Default is false.


  • Anything The computed value.

:yum: How to contribute

Have an idea? Found a bug? See how to contribute.

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Thanks! :heart:

:dizzy: Where is this library used?

If you are using this library in one of your projects, add it in this list. :sparkles:

  • ul
  • bug-killer
  • tilda
  • same-time
  • cli-box
  • bindy
  • set-or-get
  • emoji-logger
  • pixel-class
  • obj-def
  • cli-gh-cal
  • cute-logger
  • bloggify-template-renderer
  • git-package-json
  • bloggify-contact-form
  • transformer
  • git-stats
  • svg.connectable.js
  • engine-parser
  • flow-api
  • engine-builder
  • enny
  • engine-flow-types
  • engine-tools
  • ghosty
  • web-term
  • asciify-pixel
  • blah
  • bloggify-shop
  • bloggify-paths
  • bloggify-theme-renderer
  • ascii-heart
  • gh-notifier
  • love-you
  • parrot-bot
  • value-breakpoints
  • @isysd/gpm
  • gpm
  • bloggify-ws

:scroll: License

MIT © Ionică Bizău