ObjectSet

Set-like structure with custom keying function or string.

Usage

Requires node 16+ with module support.

Yarn

yarn add --dev @ayebear/object-set

NPM

npm i -D @ayebear/object-set

Examples

With string

Can use a string to grab the key automatically from the elements like element[key].

const s = new ObjectSet('id')
s.add({ id: 'foo' }) // s
s.has({ id: 'foo' }) // true
s.get({ id: 'foo' }) // { id: 'foo' }
s.delete({ id: 'foo' }) // true

With function

The function takes in the element and must return the key.

const s = new ObjectSet(e => `${e.x},${e.y}`)
s.add({ x: 10, y: 10 }) // s
s.has({ x: 10, y: 10 }) // true
s.get({ x: 10, y: 10 }) // { x: 10, y: 10 }
s.delete({ x: 10, y: 10 }) // true

Using keys

Can use keys directly in has(), get(), and delete(). These work with both string/function for ObjectSet constructor arg.

const s = new ObjectSet(e => `${e.x},${e.y}`)
s.add({ x: 10, y: 10 }) // s
s.has('10,10') // true
s.get('10,10') // { x: 10, y: 10 }
s.delete('10,10') // true

Initialize

Can pass an iterable array-like as the second arg with any type of key (string/function).

new ObjectSet('id', [{ id: 'foo' }, { id: 'bar' }])

Iteration

Iterate through set values:

const s = new ObjectSet('id', [{ id: 'foo' }, { id: 'bar' }])
for (const v of s) console.log(v)
// { id: 'foo' }
// { id: 'bar' }

Can also get iterators to internal map keys using .keys() or .entries().

Other notes

Can be other types of values besides objects, as long as your key function supports it. All common Set methods are supported, such as clear(), and some Map methods are even supported.