Some collection of functional js

functional-es6.js

const curry = f => a => b => f(a, b)
const uncurry = f => (a, b) => f(a)(b)
const papply = (f, a) => b => f(a, b)

const compose2 = (f, g) => (...args) => f(g(...args))
const compose = (...fns) => fns.reduce(compose2)
const pipe = (...fns) => fns.reduceRight(compose2)

// express.js like middle ware
// arg => fns[0](arg,null)->ret0 => fns[1](arg,ret0)->ret1 ...
const pipe2 = (fns, arg) => fns.reduce((p,c) => c(arg, p), null)

functional.js

var add1 = x=>x+1
var mul2 = x=>x*2

function currying (func, ...args) {
  return func.bind(null, ...args)
}

// https://hackernoon.com/currying-in-js-d9ddc64f162e
function curry(fn) {
  if (fn.length === 0) {
    return fn
  }
  function nest(N, args) {
    return (x) => {
      if (N - 1 === 0) {
        return fn(...args, x)
      }
      return nest(N - 1, [...args, x])
    }
  }
  return nest(fn.length, [])
}

function compose2 () {
  var funcs = arguments
  return function () {
    var args = arguments
    var self = this
    for (var i = 0; i < funcs.length; i++) {
      args = [funcs[i].apply(self, args)]
    }
    return args[0]
  }
}
// console.log(compose2(add1, mul2)(3))

function compose (funcs) {
  return function () {
    var args = arguments
    var self = this
    for (var i = 0; i < funcs.length; i++) {
      args = [funcs[i].apply(self, args)]
    }
    return args[0]
  }
}
// console.log(compose([add1, mul2])(3))