SuperMap

SuperMap class extends Map and add some methods, such as higher-order function.

Installation

$ npm i @js-commons/super-map

or

$ yarn add @js-commons/super-map

Use in your script

const SuperMap = require('@js-commons/super-map')

or

import SuperMap from '@js-commons/super-map'

Definition

Entry

Entry is expressed as array which has two elements(0:key, 1:value).

const entry1 = ['foo', 'Foo']
const entry2 = ['bar', 'Bar']
const map = SuperMap.of(entry1, entry2)
console.log(map) // {"foo" => "Foo", "bar" => "Bar"}

API

You can use Map's self methods and below additional methods.

Creation

SuperMap.empty()

const map = SuperMap.empty()
console.log(map) // {}

SuperMap.of(...entries)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map) // { 'foo' => 'Foo', 'bar' => 'Bar' }

SuperMap.from(iterable)

const map = new Map([['foo', 'Foo'], ['bar', 'Bar']])
const superMap = SuperMap.from(map)
console.log(superMap) // { 'foo' => 'Foo', 'bar' => 'Bar' }

Intermediate operation

SuperMap.peek(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const tmpMap = new Map()
const peekedMap = map.peek((v, k) => tmpMap.set(k, v))
console.log(peekedMap) // { 'foo' => 'Foo', 'bar' => 'Bar' }
console.log(tmpMap) // { 'foo' => 'Foo', 'bar' => 'Bar' }

SuperMap.peek(callback, thisArg)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const thisArg = 'baz'
const tmpMap = new Map()
const peekedMap = map.peek(function (v, k) {
  tmpMap.set(k, v + this)
}, thisArg)
console.log(peekedMap) // { 'foo' => 'Foo', 'bar' => 'Bar' }
console.log(tmpMap) // { 'foo' => 'Foobaz', 'bar' => 'Barbaz' }

SuperMap.filter(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const filteredMap = map.filter((v, k) => k.startsWith('f'))
console.log(filteredMap) // { 'foo' => 'Foo' }

SuperMap.map(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const mappedMap = map.map((v, k) => [k + '_', v + '-'])
console.log(mappedMap) // { 'foo_' => 'Foo-', 'bar_' => 'Bar-' }

SuperMap.mapEntry(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const mappedMap = map.mapEntry((v, k) => [k + '_', v + '-'])
console.log(mappedMap) // { 'foo_' => 'Foo-', 'bar_' => 'Bar-' }

SuperMap.mapKey(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const mappedMap = map.mapKey((v, k) => k + '_')
console.log(mappedMap) // { 'foo_' => 'Foo', 'bar_' => 'Bar' }

SuperMap.mapValue(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const mappedMap = map.mapValue((v, k) => v + '-')
console.log(mappedMap) // { 'foo' => 'Foo-', 'bar' => 'Bar-' }

Terminal operation

SuperMap.find(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const entry = map.find((v, k) => k.startsWith('f'))
console.log(entry) // [ 'foo', 'Foo' ]

const map = SuperMap.empty()
const entry = map.find((v, k) => k.startsWith('f'))
console.log(entry) // undefined

SuperMap.findEntry(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const entry = map.findEntry((v, k) => k.startsWith('f'))
console.log(entry) // [ 'foo', 'Foo' ]

const map = SuperMap.empty()
const entry = map.findEntry((v, k) => k.startsWith('f'))
console.log(entry) // undefined

SuperMap.findKey(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const key = map.findKey((v, k) => k.startsWith('f'))
console.log(key) // foo

const map = SuperMap.empty()
const key = map.findKey((v, k) => k.startsWith('f'))
console.log(key) // undefined

SuperMap.findValue(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const value = map.findValue((v, k) => k.startsWith('f'))
console.log(value) // Foo

const map = SuperMap.empty()
const value = map.findValue((v, k) => k.startsWith('f'))
console.log(value) // undefined

SuperMap.hasEntry(entry)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.hasEntry(['foo', 'Foo'])) // true

const map = SuperMap.empty()
console.log(map.hasEntry(['foo', 'Foo'])) // false

SuperMap.hasKey(key)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.hasKey('foo')) // true

const map = SuperMap.empty()
console.log(map.hasKey('foo')) // false

SuperMap.hasValue(value)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.hasValue('Foo')) // true

const map = SuperMap.empty()
console.log(map.hasValue('Foo')) // false

SuperMap.some(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.some((v, k) => k.startsWith('f'))) // true

const map = SuperMap.empty()
console.log(map.some((v, k) => k.startsWith('f'))) // false

SuperMap.every(callback)

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.every((v, k) => k.length === 3)) // true

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.every((v, k) => k.startsWith('f'))) // false

SuperMap.isEmpty()

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.isEmpty()) // false

const map = SuperMap.empty()
console.log(map.isEmpty()) // true

SuperMap.isNotEmpty()

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
console.log(map.isNotEmpty()) // true

const map = SuperMap.empty()
console.log(map.isNotEmpty()) // false

SuperMap.toEntries()

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const entries = map.toEntries()
console.log(entries) // [ [ 'foo', 'Foo' ], [ 'bar', 'Bar' ] ]

SuperMap.toKeys()

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const keys = map.toKeys()
console.log(keys) // [ 'foo', 'bar' ]

SuperMap.toValues()

const map = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const values = map.toValues()
console.log(values) // [ 'Foo', 'Bar' ]

SuperMap.toMap()

const superMap = SuperMap.of(['foo', 'Foo'], ['bar', 'Bar'])
const map = superMap.toMap()
console.log(map) // { 'foo' => 'Foo', 'bar' => 'Bar' }