comparison of lazy evaluation

main.js

const _ = require('lodash');
const t = require('transducers.js');


const arrayofRandoms = randomCeil => length =>
  Array.from({length: length}, (v, i) =>
    Math.floor(Math.random() * randomCeil));
  
const arrOfMillion = arrayofRandoms(100)(1e6);
const tripleIt = (el) => el * 3;
const isEven = (el) => el % 2 === 0;

const timeIt = (name, fn) => {
  console.time(name);
  fn();
  console.timeEnd(name);
}

/**
 * Native methods
 */
timeIt('million - native', () => {
  arrOfMillion
    .map(tripleIt)
    .filter(isEven)
})

timeIt('million - native x 2', () => {
  arrOfMillion
    .map(tripleIt)
    .map(tripleIt)
    .filter(isEven)
})

timeIt('million - native x 4', () => {
  arrOfMillion
    .map(tripleIt)
    .map(tripleIt)
    .map(tripleIt)
    .map(tripleIt)
    .filter(isEven)
})

/**
 * Lodash version
 */
timeIt('million - lodash', () => {
  _(arrOfMillion)
    .map(tripleIt)
    .filter(isEven)
    .value()
})

timeIt('million - lodash x 2', () => {
  _(arrOfMillion)
    .map(tripleIt)
    .map(tripleIt)
    .filter(isEven)
    .value()
})

timeIt('million - lodash x 4', () => {
  _(arrOfMillion)
    .map(tripleIt)
    .map(tripleIt)
    .map(tripleIt)
    .map(tripleIt)
    .filter(isEven)
    .value()
})

/**
 * transducers
 */

timeIt('million - transducers', () => {
  t.seq(
    arrOfMillion,
    t.compose(
      t.filter(isEven),
      t.map(tripleIt)
    )
  )
})

timeIt('million - transducers x 2', () => {
  t.seq(
    arrOfMillion,
    t.compose(
      t.filter(isEven),
      t.map(tripleIt),
      t.map(tripleIt)
    )
  )
})

timeIt('million - transducers x 4', () => {
  t.seq(
    arrOfMillion,
    t.compose(
      t.filter(isEven),
      t.map(tripleIt),
      t.map(tripleIt),
      t.map(tripleIt),
      t.map(tripleIt)
    )
  )
})

// million - native: 210.871ms
// million - native x 2: 302.492ms
// million - native x 4: 492.038ms
// million - lodash: 41.545ms
// million - lodash x 2: 45.860ms
// million - lodash x 4: 52.093ms
// million - transducers: 123.363ms
// million - transducers x 2: 131.208ms
// million - transducers x 4: 134.362ms