comprehension v1.1.1

Comprehension.js

Using

Array with static elements

c$(3, () => "asd")

[ "asd", "asd", "asd" ]

same as new Array(3).fill("asd")

Incremented elements

c$(5)

[ 0, 1, 2, 3, 4 ]

same as new Array(5).fill(0).map((_, i) => i)

Incrementing value

c$({ count: 5, step: 3 })

[ 0, 3, 6, 9, 12 ]

same as new Array(5).fill(0).map((_, i) => 3 * i)

Incrementing from-to

c$({ from: 4, to: 9 })

[ 4, 5, 6, 7, 8, 9 ]

same as new Array(6).fill(0).map((_, i) => i + 4)

Negative step support

c$({ from: 4, count: 5, step: -3 })

[ 4, 1, -2, -5, -8 ]

same as new Array(5).fill(0).map((_, i) => i * -3 + 4)

Mapping

c$({ from: 3, count: 4 }, i => 2 ** i)

[ 8, 16, 32, 64 ]

same as new Array(4).fill(0).map((_, i) => 2 ** (i + 3))

Index independent

c$({ count: 5 }, () => Math.floor(Math.random() * 8))

[ 2, 3, 6, 4, 2 ]

same as new Array(5).fill(0).map(() => Math.floor(Math.random() * 8))

Example of usage

Asynchronously creates folders with names "folder_100", "folder_106", ... , "folder_220" in directory "dist".

import c$ from "comprehension";
import { mkdirp } from "fs-extra";

async function createIndexedDirectory(index: number): string {
	const path = `${__dirname}/dist/folder_${index}`;
	await mkdirp(path);
	return path;
}

// ...

await mkdirp(`${__dirname}/dist`);
const promises = c$(
	{ from: 100, to: 220, step: 6 },
	createIndexedDirectory,
);
console.log(await Promise.all(promises));