@bitty/nullish

Nullish helper functions and types for TypeScript.

• 📦 Distributions in ESM, CommonJS, UMD and UMD minified formats.

• ⚡ Lightweight:

  • Weighs less than 0.2KB (min + gzip).
  • Tree-shakeable.
  • Side-effects free.

• 🔋 Bateries included:

  • No dependencies.
  • Its not based on newer browser's APIs or es2015+ features.

• 🏷 Safe:

  • JSDocs and type declarations for IDEs and editor's autocomplete/intellisense.
  • Made with TypeScript as strict as possible.
  • Unit tests with AVA.

Installation

This library is published in the NPM registry and can be installed using any compatible package manager.

npm install @bitty/nullish --save

# For Yarn, use the command below.
yarn add @bitty/nullish

Installation from CDN

This module has a UMD bundle available through JSDelivr and Unpkg CDNs.

<!-- For UNPKG use the code below. -->
<script src="https://unpkg.com/@bitty/nullish"></script>

<!-- For JSDelivr use the code below. -->
<script src="https://cdn.jsdelivr.net/npm/@bitty/nullish"></script>

<script>
  // UMD module is exposed through the "isNullish" global function.
  console.log(isNullish);
  //=> "[Function: isNullish]"

  console.log(isNullish(null));
  //=> true
</script>

Getting Stated

This module default exports isNullish, which is a predicate function that checks if value is nullish.

import isNullish from '@bitty/pipe';

isNullish(null);
//=> true

isNullish(undefined);
//=> true

isNullish(undefined as void);
//=> true

isNullish(NaN);
//=> false

We also exports NonNullish and Nullish types.

• Nullish is simply an union of null, void and undefined types.

  import { Nullish } from '@bitty/nullish';
  
  let nullish: Nullish;
  nullish = null;
  nullish = undefined;
  nullish = undefined as void;
  
  nullish = false;
  //=> throws "Type 'false' is not assignable to type 'Nullish'.".

• NonNullish<T> is a type helper that removes nullish types.

  import { NonNullish } from '@bitty/nullish';
  
  type Value = string | null | undefined;
  
  const value: NonNullish<Value> = null;
  //=> throws "Type 'null' is not assignable to type 'string'.".

License

Released under MIT License.