ljharb / proposal-array-compact

A proposal for adding a `compact()` method to Arrays

proposal-array-compact

A proposal to create a more compact array, by discarding falsey values

const array = [0, 1, false, 2, '', 3]

array.compact()
// =>  [1, 2 3]

Champions

• Keith Cirkel (@keithamus)

Status

Current Stage: 0

Motivation

Compacting an Array to only truthy values is a common operation. It's usually handled by calling filter with an identity function (44k results):

array.filter(i => i)

or by passing the Boolean value as a predicate function:

array.filter(Boolean)

Both of these can be somewhat tricky to reason about, and both styles can be used in the same codebase to make matters more confusing.

Lodash includes _.compact() which as a standalone dependency receives ~400,000 downloads per week.

Sugar includes .compact(all) which may cause webcompat issues - as the all boolean (defaulting to false) determines if elements removed should be falsey (when true) or nullish (when false).

Other languages

• Ruby has a .compact method, which wil return an Array with all nil elements removed

Polyfill

• None as of yet.