Defract

A modern JavaScript utility library that delivers functions for data structures, calculations, and more!

Made by intfract

Install

npm i defract

Import

CJS

const _ = require('defract')

ESM

import _ from "defract"

Integrate

This module offers the powerful _.must and _.countif functions. It allows dynamic filtration and distillation of arrays of objects. More functions will be added to defract in the future, but some of the best are shown below.

console.log(_.chunk([0, 'text', [], {}], 3))
// [[0, 'text', []], [{}]]

console.log(_.eq([], []))
console.log(_.eq([0, 'text'], [0, 'text']))
console.log(_.eq([0, 'text', [], {}], [0, 'text', [], {}]))
console.log(_.eq({}, {}))
console.log(_.eq({ a: 0 }, { a: 0 }))
console.log(_.eq({ a: 0, b: [] }, { a: 0, b: [] }))
// true

const users = [
  {
    name: 'John',
    age: 18,
    deleted: false
  },
  {
    name: 'Jane',
    age: 13,
    deleted: false
  },
  {
    name: 'Bob',
    age: 69,
    deleted: true
  },
]

console.log(_.countif(users, '.age > 13'))
// 2
console.log(_.countif(users, ['&&', '.age > 13', '.deleted === false']))
// 1

console.log(_.filter(users, _.must({ age: '> 16' })))
// [{ name: 'John', age: 18, deleted: false }, { name: 'Bob', age: 69, deleted: true }]
console.log(_.filter(users, { age: 13 })) // _.matches shorthand
// [{ name: 'Jane', age: 18, deleted: false }]
console.log(_.filter(users, ['name', 'John'])) // _.matchesProperty shorthand
// [{ name: 'John', age: 18, deleted: false }]
console.log(_.filter(users, 'deleted')) // _.property shorthand
// [{ name: 'Bob', age: 69, deleted: true }]

console.log(_.find(users, _.must({ age: '> 16' })))
// { name: 'John', age: 18, deleted: false }
console.log(_.find(users, { age: 13 })) // _.matches shorthand
// { name: 'Jane', age: 18, deleted: false }
console.log(_.find(users, ['name', 'John'])) // _.matchesProperty shorthand
// { name: 'John', age: 18, deleted: false }
console.log(_.find(users, 'deleted')) // _.property shorthand
// { name: 'Bob', age: 69, deleted: true }

console.log(_.findIndexes(users, _.must({ age: '> 16' })))
// [0, 2]
console.log(_.findIndexes(users, { age: 13 })) // _.matches shorthand
// [1]
console.log(_.findIndexes(users, ['name', 'John'])) // _.matchesProperty shorthand
// [0]
console.log(_.findIndexes(users, 'deleted')) // _.property shorthand
// [2]

console.log(_.distill(users, _.must({ age: ['&&', '>= 13', '<= 18'] })))
// [[John, Jane], [Bob]]
console.log(_.distill(users, { age: 18 })) // _.matches shorthand
// Array of length 2
console.log(_.distill(users, ['name', 'John'])) // _.matchesProperty shorthand
// Array of length 2
console.log(_.distill(users, 'deleted')) // _.property shorthand
// Array of length 2

console.log(_.unite([0, 'text', [], {}], [0, 'text'], [0, 'text', [], {}]))
// [0, 'text', [], {}, 0, 'text', 0, 'text', [], {}]
console.log(_.unite([0, 'text', [], {}], 'string'))
// [0, 'text', [], {}, 'string']

console.log(_.subtract([0, 'text', [], {}, [0, 1]], [0, []], [{}]))
// ['text', [0, 1]]

console.log(_.intersect([0, 'text', [], {}], [0, 'text'], ['text', {}]))
// ['text', 'text', 'text']

console.log(_.exclude([0, 'text', [], {}], [0, 'text'], ['text', {}]))
// [[]]

console.log(_.mapKeys({ apple: 'alpha', ball: 'beta' }, k => k[0]))
// { a: 'alpha', b: 'beta' }

console.log(_.mapValues({ apple: 'alpha', ball: 'beta' }, v => v[0]))
// { apple: 'a', ball: 'b' }

console.log(_.unique([0, 'text', [], {}, 'text', {}]))
// [0, 'text', [], {}]

for (let num of _.range(10, 0, 2)) {
  console.log(num)
}

console.log(_.search([[], {}, 'a', 'b', 'c'], {})) // binary search
// 1

console.log(_.shuffle([0, 1, 2, 3], 2))
// [2, 3, 0, 1]

console.log(_.zip(['id', 0, 1, 2], ['username', 'qaxt', 'bob', 'npm']))
// [['id', 'username'], [0, 'qaxt'], [1, 'bob'], [2, 'npm']]

console.log(_.indexes([0, 'text', [], {}, 'text', ['text']], 'text'))
// [1, 4]

console.log(_.last([0, 'text', [], {}]))
// {}
console.log(_.last(_.indexes([0, 'text', [], {}, 'text', ['text']], 'text')))
// 4

console.log(_.nth([0, 'text', [], {}], -1))
// {}

console.log(_.factors(-12))
// [1, -12, -1, 12, 2, -6, -2, 6, 3, -4, -3, 4]

console.log(_.insert([0, 'text', [], {}], 2, { a: 0 }))
// [0, 'text', { a: 0 }, [], {}]

console.log(_.fromPairs([['a', 0], ['b', []]]))
// { a: 0, b: [] }

console.log(_.iterate([['id', 0, 1, 2], ['username', 'qaxt', 'bob', 'npm']], (a) => {
  return a
}))
// same output as _.zip(['id', 0, 1, 2], ['username', 'qaxt', 'bob', 'npm'])

const space = _.ndarray(2, 3)
console.log(space)
/*
{
  length: 2,
  dimensions: 3,
  data: [
    0, 1, 2, 3,
    4, 5, 6, 7
  ]
} 
*/

console.log(_.ndindex([1, 0, 1], space.length))
// 5
console.log(space.data[_.ndindex([1, 0, 1], space.length)])
// [1, 0, 1]

console.log(_.ndpoint(5, space.length, space.dimensions))
// [1, 0, 1]