node-parse-numeric-range

Parses expressions like 1-10,20-30. Returns an energetic (as opposed to lazy) array.

Supported Expressions

Comprehensive supported expression examples:

| Expression | result | |:----------:|:------------:| | | [] | | 1 | [1] | | 1,2 | [1,2] | | -10 | [-10] | | -3,-3 |[-3, -3] | | -1-2,-2 |[-1,0,1,2,-2] | | -1--2 |[-1,-2] | | -1..2,-2 |[-1,0,1,2,-2] | | -1...3,-2 |[-1,0,1,2,-2] | | 1⋯3 |[1,2] | | 1…3 |[1,2] | | 1‥3 |[1,2,3] |

What's this useful for? Well, letting users input these sorts of things and then making them programmatically useful.

Usage

First, npm install parse-numeric-range.

const rangeParser = require("parse-numeric-range");

const numbers = rangeParser("4,6,8-10,12,14..16,18,20...23");

console.log(
  `The first ${numbers.length} composite numbers are: ${numbers.join(", ")}`,
);

ES6

import rangeParser from "parse-numeric-range";

const numbers = rangeParser("4,6,8-10,12,14..16,18,20...23");

console.log(
  `The first ${numbers.length} composite numbers are: ${numbers.join(", ")}`,
);