https://github.com/iplaylf2/each-once
For each item in collection once.
https://github.com/iplaylf2/each-once
collection stream transduce typescript
Last synced: 2 months ago
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For each item in collection once.
- Host: GitHub
- URL: https://github.com/iplaylf2/each-once
- Owner: iplaylf2
- License: bsd-3-clause
- Created: 2021-02-22T03:02:53.000Z (over 4 years ago)
- Default Branch: main
- Last Pushed: 2021-03-05T04:42:58.000Z (about 4 years ago)
- Last Synced: 2025-02-15T21:47:22.692Z (3 months ago)
- Topics: collection, stream, transduce, typescript
- Language: TypeScript
- Homepage:
- Size: 130 KB
- Stars: 1
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
# each-once
For each item in collection once.
English | [中文](https://github.com/Iplaylf2/each-once/blob/main/doc/README.cn.md)
-
## feature
- Easy to use.
- Data structure is basic.
- Efficient.
## install
``` bash
npm install each-once
```
## usage
``` typescript
import { combine, map, filter, take, reduce } from "each-once";
const tf = combine(
map((x: number) => x * 2),
filter((x: number) => x % 4 === 0),
take(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](https://github.com/Iplaylf2/each-once/blob/main/debug/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](https://github.com/Iplaylf2/each-once/blob/main/doc/document.md)