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optionize

:sparkles: Optional values for JavaScript

Why?

Because null is evil for a variety of reasons and other languages, such as Scala, address this issue through a simple Option type, where any boxed value is either Some or None. This article covers the generic behaviors of Some and None using the Scala API.

How?

optionize simulates this behavior in JavaScript with an extremely simple and idiomatic API:

get: returns the value without consideration of Some/None
getOrElse: returns the value if it is Some, otherwise returns the provided fallback
map: maps the provided function against the value if it is Some
forEach: applies the provided function to the value if it is Some

That's it!

Example

By declaring values as either Some or None, you no longer need toconditionally access your data depending on if a value is present or not and can work with a consistent interface:

import { none, some } from 'optionize'

function badFoo (bar) {
  if (bar) {
    return bar.baz
  }

  return {}
}

function goodFoo (bar) {
  return bar.getOrElse({}).baz
}

badFoo({ baz: 'boo' }) // returns 'boo'
badFoo(null) // returns {}

goodFoo(some({ baz: 'win' })) // returns 'win'
goodFoo(none) // returns {}

Downsides

Nothing is perfect and everything comes with tradeoffs. Here's what isn't great about using Some and None:

Doesn't play with truthy/falsy, so you can't utilize || or &&
Due to JavaScript's limited pattern matching abilities, you still end up using if or ternary conditions to wrap a value as either Some or None (this can probably be improved with a simple implicit method, TODO)