README.md

fast-collection

Small library making javascript object-array manipulation fast, easy, and giving some useful tools for an in-memory database based on javascript collections.

---

Getting start

This library extends Array javascript global object, so every methods and properties of Array can be used.

Examples

import Collection from 'fast-collection'

const arrayObject = [
  { id: 'VGmMSEdRE08', name: 'Jyn Erso', species: 'Human', jedi: false },
  { id: '7Mw8rRmQBPJ', name: 'D-O', species: 'Droid', jedi: false },
  { id: 'igZy1rU2_ap', name: 'Aayla Secura', species: 'Twi’lek', jedi: true },
  { id: 'Enh1bod3qHZ', name: 'Ahsoka Tano', species: 'Togruta', jedi: true },
  { id: '7wllhuMz9tr', name: 'Yoda', species: 'Unkown', jedi: true }
]

const collection = Collection.from(arrayObject)

Retrieve all being jedi AND Togruta and select only id, name properties

collection.retrieve({ jedi: true, species: 'Togruta' }).select('id', 'name')
// return [{ id: 'Enh1bod3qHZ', name: 'Ahsoka Tano' }]

Retrieve all not being jedi OR Unknown species and select only name property

collection.retrieve({ jedi: false }, { species: 'Unknown' }).select('name')
// return [{ name: 'Jyn Erso' }, { name: 'D-O' }, { name: 'Yoda'}]

Retrieve first being with the lastname Tano and select only name property

collection.retrieveOne({ name: /Tano$/ }).select('name')
// return [{ name: 'Ahsoka Tano' }]

Retrieve index with id property

collection.retrieveIndex({ id: '7Mw8rRmQBPJ' })
// return 1

Retrieve values of a string, number or boolean property

collection.valuesOf('species')
// return ['Human', 'Droid', 'Togruta', 'Twi’lek', 'Unknown']

collection.valuesOf('jedi')
// return [false, true]

Limit retrieved items with slice

// limit 2 items from the first item found
collection.retrieve({ jedi: true }).select('name').slice(0, 2)
// return [{ name: 'Aayla Secura' }, { name: 'Ahsoka Tano' }]

Insert to first with ES spread operator or splice

// faster
[
  {
    id: 'oE6iC-2AW9T_2t5yQz2eS',
    name: 'Rey Skywalker',
    species: 'Human',
    jedi: true
  },
  ...collection
]

// slower
collection.splice(0, 0, {
  id: 'oE6iC-2AW9T_2t5yQz2eS',
  name: 'Rey Skywalker',
  species: 'Human',
  jedi: true
})

Insert to last with push

// fastest
collection.push({
  id: 'oE6iC-2AW9T_2t5yQz2eS',
  name: 'Rey Skywalker',
  species: 'Human',
  jedi: true
})

Update and Delete with retrieveIndex and splice

// update - delete and replace
const index = collection.retrieveIndex({ id: '7Mw8rRmQBPJ' })
collection.splice(index, 1, {...collection[index], { name: 'R2D2' }})

// delete
const index = collection.retrieveIndex({ id: '7wllhuMz9tr' })
collection.splice(index, 1)

---

API

Collection.prototype.retrieve()

Syntax

col.retrieve(filter0[, filter1[, ...[, filterN]]])

Parameters

filterN Object containing properties filter, type of property values can be string, boolean, number, function or Regexp.

Return value

Reduced Collection instance.

Collection.prototype.retrieveOne()

Syntax

col.retrieveOne(filter)

Parameters

filter Object containing properties filter, type of property values can be string, boolean, number, function or Regexp.

Return value

New Collection instance with the first object found.

Collection.prototype.retrieveIndex()

Syntax

col.retrieveIndex(filter)

Parameters

filter Object containing properties filter, type of property values can be string, boolean, number, function or Regexp.

Return value

Index number found of the Collection instance.

Collection.prototype.valuesOf()

Syntax

col.valuesOf(property)

Parameters

property Property name of Collection instance items. Type of property values can only be boolean, string, or number.

Return value

Array instance with the list of values found.

Collection.prototype.select()

Syntax

col.select(property0[, property1[, ...[, propertyN]]])

Parameters

propertyN Property name of Collection instance items.

Return value

Cloned Collection instance with the selected properties.