RunKit + npm: @codibre/fluent-iterable

const { fluent, interval } = require('@codibre/fluent-iterable'); const rxjs = require('rxjs'); const rxjsOp = require('rxjs/operators'); const Benchmark = require('benchmark'); const ITEMS = 100000; const FLAT_FACTOR = 10; const MULTIPLIER1 = 3; const MULTIPLIER2 = 2; const QUOTIENT = 5; const TAKE = 2000; const benchmarkSuite = new Benchmark.Suite(); function interval2(init, final) { const items = []; for(let i = init; i <= final; i++) { items.push(i); } return items; } function *map1(it) { for (const x of it) { yield x * MULTIPLIER1; } } function *map2(it) { for (const x of it) { yield x * MULTIPLIER2; } } function *filter1(it) { for (const x of it) { if (x % QUOTIENT === 0) { yield x; } } } function *take1(it) { let count = 0; for (const x of it) { count++; if (count >= TAKE) { break; } yield interval2(x, x + FLAT_FACTOR); } } function *map3(it) { for (const x of it) { yield interval2(x, x + FLAT_FACTOR); } } let log = ''; benchmarkSuite.add('fluent', () => { fluent(interval(1, ITEMS)) .map((x) => x * MULTIPLIER1) .map((x) => x * MULTIPLIER2) .filter((x) => x % QUOTIENT === 0) .map((x) => interval2(x, x + FLAT_FACTOR)) .take(TAKE) .forEach((x) => x.join(',')); }).add('array operation chain', () => { interval2(1, ITEMS).map((x) => x * MULTIPLIER1) .map((x) => x * MULTIPLIER2) .filter((x) => x % QUOTIENT === 0) .map((x) => interval2(x, x + FLAT_FACTOR)) .filter((_x, i) => i < TAKE) .map((x) => x.join(',')); }).add('native iterable', () => { const it0 = interval2(1, ITEMS); const it = map3(take1(filter1(map2(map1(it0))))); for (const x of it) { x.join(','); } }).add('rxjs', () => { return rxjs.from(interval2(1, ITEMS)) .pipe( rxjsOp.map((x) => x * MULTIPLIER1), rxjsOp.map((x) => x * MULTIPLIER2), rxjsOp.filter((x) => x % QUOTIENT === 0), rxjsOp.map((x) => interval2(x, x + FLAT_FACTOR)), rxjsOp.take(TAKE), rxjsOp.map((x) => x.join(',')), ).toPromise(); }).on('cycle', function(event) { console.log(String(event.target)); }).on('complete', function() { log = this.filter('fastest').map('name'); }).run(); `Fastest is ${log}`