each-once

For each item in collection once.

English | 中文

feature

• Easy to use.
• Data structure is basic.
• Efficient.

install

npm install each-once

usage

import { combine, map, filter, take, reduce } from "each-once";

const tf = combine(
  map((x: number) => x * 2),
  filter((x: number) => x % 4 === 0),
  take<number>(10)
);

const transduce = reduce((r, x) => r + x, 0, tf);

const s = function* () {
  let x = 0;
  while (true) {
    yield x++;
  }
};

const result = transduce(s()); // transduce([0, 1, 2...])

console.log(result); // 180

benchmark

Benchmark which map n times and reduce once. from benchmark.ts

array

map times \ ops/sec \ array length	100	1000	10000	100000
2	1193319	28799	2688	195
3	199984	22248	2166	155
4	167229	17363	1685	126
5	144092	14313	1356	96.84

each-once

map times \ ops/sec \ array length	100	1000	10000	100000
2	524905	50661	5370	562
3	373222	38385	4066	397
4	284126	31329	3133	315
5	233850	25214	2499	242

each-once is more efficient!

document