nanoption

Tiny (220 bytes), zero dependency wrapper for nullable values.

TL;RD

``js
// Without nanoption
const parsedInput = nullableVar != null
? parseInt(nullableVar) + 12
: 1

calculate(parsedInput)

// With nanoption
import { Option } from 'nanoption'

const parsedInput = Option.of(nullableVar)
.map(v => parseInt(v))
.map(v => v + 12)
.getOrElse(1)

calculate(parsedInput)
`

Installation



`sh
yarn add nanoption
`

Or if you prefer npm:

`sh
npm i nanoption
`

Motivation

It JS in some cases we can get an error Cannot do something of undefined/null. This library explicitly works with nullable values and provide clear interface for it.

Also, library support TypeSciript as first-class citizen and do some checks in complie time. For example:
`ts
import { Option } from 'nanoption'

// #map
Option.of(2).map(_ => _ * 2) // Some(4)
Option.of().map(() => 2) // None (known at compile time)

// #get
Option.of(3).get() // 3
Option.of().get() // COMPILE ERROR! Can't call get() on None
`

Of course, you can use JavaScript without TypeScript, but it's not as fun.

Now Optional Chaining Proposal only on stage 1, but very useful. This library give ECMAScript-version independent alternative for it.

API

`ts
import { Option } from 'nanoption'

// Create an option
Option.of(3) // Some(3)
Option.of('abc') // Some('abc')
Option.of(null) // None
Option.of(undefined) // None

// #map
Option.of(2).map(_ => _ * 2) // Some(4)
Option.of().map(() => 2) // None

// #flatMap
Option.of(3).flatMap(_ => Option.of(_ * 2)) // Some(6)
Option.of().flatMap(() => Option.of(2)) // None

// #get
Option.of(3).get() // 3
Option.of().get() // throw Exception

// #getOrElse
Option.of(1).getOrElse(2) // 1
Option.of(null).getOrElse(2) // 2

// #isEmpty
Option.of(2).isEmpty() // false
Option.of().isEmpty() // true

// #nonEmpty
Option.of(2).nonEmpty() // true
Option.of().nonEmpty() // false

// #toString
Option.of(2).toString() // "Some(2)"
Option.of().toString() // "None"
``

Alternatives

+ tsoption is Fantasyland-compliant, but it requires 2-3 times more space.