@tehshrike/regexparam

regexparam with longer variable names and support for custom regex patterns.

A tiny (332B) utility that converts route patterns into RegExp. Limited alternative to path-to-regexp 🙇

With @tehshrike/regexparam, you may turn a pathing string (eg, /users/:id) into a regular expression.

An object with shape of { keys, pattern } is returned, where pattern is the RegExp and keys is an array of your parameter name(s) in the order that they appeared.

Unlike path-to-regexp, this module does not create a keys dictionary, nor mutate an existing variable. Also, this only ships a parser, which only accept strings. Similarly, and most importantly, @tehshrike/regexparam only handles basic pathing operators:

• Static (/foo, /foo/bar)
• Parameter (/:title, /books/:title, /books/:genre/:title)
• Optional Parameters (/:title?, /books/:title?, /books/:genre/:title?)
• Wildcards (*, /books/*, /books/:genre/*)
• Regex Parameters (/user/:userId(\\d+))

Lastly, please note that while this route-parser is not slow, you should use matchit or trouter if performance is of critical importance. This is especially true for backend/server scenarios!

This module exposes two module definitions:

• ES Module: dist/regexparam.mjs
• CommonJS: dist/regexparam.js

Install

$ npm install --save @tehshrike/regexparam

Usage

const regexparam = require('@tehshrike/regexparam');

let foo = regexparam('users/*')
foo.keys // => ['wild']
foo.pattern // => /^\/users\/(.*)(?:\/)?\/?$/i

let bar = regexparam('/books/:genre/:title?')
bar.keys // => ['genre', 'title']
bar.pattern // => /^\/books\/([^\/]+?)(?:\/([^\/]+?))?(?:\/)?\/?$/i

bar.pattern.test('/books/horror') //=> true
bar.pattern.test('/books/horror/goosebumps') //=> true

// Example param-assignment
function exec(path, { keys, pattern }) {
	const matches = pattern.exec(path)
	const out = {}
	keys.forEach((key, i) => {
		out[key] = matches[i + 1] || null
	})

	return out
}

exec('/books/horror', bar) //=> { genre:'horror', title:null }

exec('/books/horror/goosebumps', bar) //=> { genre:'horror', title:'goosebumps' }

Important: When matching/testing against a generated RegExp, your path must begin with a leading slash ("/")!

API

regexparam(str)

Returns: Object

str

Type: String

The route/pathing string to convert.

Note: It does not matter if your str begins with a / — it will be added if missing.

License

MIT © Luke Edwards