rregex

A dependency-free WebAssembly build of Rust Regex for Javascript

• Why Rust Regex
• Install
• Supported Runtimes
• API
  • RRegex
  • RRegexSet
  • Match
  • Captures
  • escape
• Benchmarks
• Known Issues

Why Rust Regex

Rust has a powerful Regex library with a lot of features that don't exists en the standard Regex object

See the official documentation for more detail

Install

  # NPM
  npm install rregex

  # Yarn
  yarn add rregex

  # PNPM
  pnpm add rregex

  # Deno
  deno add @rregex/rregex

  # JSR
  npx jsr add @rregex/rregex

Supported Runtimes

This package includes builds for multiple runtimes

| Runtime | Import | version | | ------------------ | ------------------------------------------------------- | ---------- | | Node.js (esm) | import { RRegex, RRegexSet } from 'rregex' | * | | Node.js (commonjs) | const { RRegex, RRegexSet } = require('rregex') | * | | Deno | import { RRegex, RRegexSet } from '@rregex/rregex' | >=1.10.8 | | Bun | import { RRegex, RRegexSet } from '@rregex/rregex' | >=1.10.8 | | Cloudflare Workers | import { RRegex, RRegexSet } from 'rregex/lib/cf.mjs' | >=1.10.8 | | Browser | TODO | | | Standalone | TODO | |

Benchmarks

In general terms rregex is at least 1 order of magnitud slower than the native RegExp object, but still have a good performance. Unless you required some of the features that rregex provides, you should always consider using the native RegExp object

Benchmarks are executed using test/deno.bench.mjs, and test/node.bench.mjs

Email

| benchmark | time (avg) | iter/s | | --------- | -------------: | ------: | | RegExp | 342.91 µs/iter | 2,916.2 | | RRegex | 7.27 ms/iter | 137.6 |

summary: RegExp is 21.19x faster than RRegex

IP

| benchmark | time (avg) | iter/s | | --------- | ------------: | -------: | | RegExp | 72.63 µs/iter | 13,767.7 | | RRegex | 7.02 ms/iter | 142.5 |

summary: RegExp is 96.59x faster than RRegex

URI

| benchmark | time (avg) | iter/s | | --------- | -------------: | ----------: | | RegExp | 688.79 ns/iter | 1,451,825.0 | | RRegex | 22.52 ms/iter | 44.4 |

summary: RegExp is 32689.42x faster than RRegex

| benckmarks | benckmarks | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | | | | |

Note: In order to compare with native regex these benchmarks follow the mariomka/regex-benchmark structure

Known Issues

If you call splitn(text, limit) and the expected result length is equal to limit - 1 the result will include an extra item "", this behavior does not happen if limit es greater. fixed at >=1.3

const regex = new RRegex(",");
expect(regex.splitn("a,b,c", 0)).toEqual([]);
expect(regex.splitn("a,b,c", 1)).toEqual(["a,b,c"]);
expect(regex.splitn("a,b,c", 2)).toEqual(["a", "b,c"]);
expect(regex.splitn("a,b,c", 3)).toEqual(["a", "b", "c"]);

// This result includes an unexpected extra item
expect(regex.splitn("a,b,c", 4)).toEqual(["a", "b", "c", ""]);
expect(regex.splitn("a,b,c", 5)).toEqual(["a", "b", "c"]);

expect(regex.splitn("abc", 0)).toEqual([]);
expect(regex.splitn("abc", 1)).toEqual(["abc"]);

// This result includes an unexpected extra item
expect(regex.splitn("abc", 2)).toEqual(["abc", ""]);
expect(regex.splitn("abc", 3)).toEqual(["abc"]);