immutable array functions for ES6

immutable-array.js

// https://twitter.com/lukejacksonn/status/928244319760220160

module.exports = {
  clone: x => [...x],
  push: y => x => [...x, y],
  pop: x => x.slice(0, -1),
  unshift: y => x => [y, ...x],
  shift: x => x.slice(1),
  sort: f => x => [...x].sort(f),
  delete: i => x => [...x.slice(0, i), ...x.slice(i + 1)],
  splice: (s, c, ...y) => x => [...x.slice(0, s), ...y, ...x.slice(s + c)]
}