pcre2-wasm-universal

A universal (Node.js + browser) fork of @stephen-riley/pcre2-wasm.

This package provides PCRE2 (Perl Compatible Regular Expressions 2) compiled to WebAssembly, modified to work in both Node.js and browser environments.

Changes from Original

The original @stephen-riley/pcre2-wasm package has several Node.js-specific dependencies that prevent it from working in browsers:

1. libpcre2.js - Uses require("path") and __dirname to locate WASM file
2. PCRE.js - Uses require("assert") for assertions
3. PCRE.js - Uses require("util").TextDecoder instead of browser-native TextDecoder
4. PCRE.js - Uses Buffer.from(str, 'utf16le') for UTF-16 encoding

This fork addresses all these issues:

• Removed Node.js-specific WASM file locator (browsers use scriptDirectory detection)
• Replaced require("assert") with inline assertion function
• Uses browser-native TextDecoder('utf-16le')
• Replaced Buffer.from() with custom encodeUTF16LE() function
• Converted to ESM module format

Installation

npm install pcre2-wasm-universal

Usage

import PCRE from 'pcre2-wasm-universal';

// Initialize PCRE2 (required before first use)
await PCRE.init();

// Create a regex pattern
const regex = new PCRE('\\d+');

// Match against a string
const result = regex.match('abc123def');
console.log(result[0].match); // "123"

// Clean up when done
regex.destroy();

WASM File Location

In browser environments, the WASM file (libpcre2.wasm) needs to be served from the same directory as libpcre2.js. If using a bundler like Vite, you may need to configure it to handle the WASM file correctly.

For Vite, you can use the ?url import suffix or configure assetsInclude in vite.config.js:

// vite.config.js
export default {
  assetsInclude: ['**/*.wasm'],
  optimizeDeps: {
    exclude: ['pcre2-wasm-universal']
  }
}

API

PCRE.init()

Initializes the PCRE2 WASM module. Must be called before creating any PCRE instances.

new PCRE(pattern, flags)

Creates a new PCRE regex instance.

• pattern - The regex pattern string
• flags - Optional flags string

pcre.match(subject, start)

Matches the pattern against the subject string.

• subject - The string to match against
• start - Optional starting offset (default: 0)

Returns match object with capture groups, or null if no match.

pcre.matchAll(subject)

Returns all matches in the subject string.

pcre.substitute(subject, replacement, startOffset, options)

Performs regex substitution.

pcre.destroy()

Frees WASM memory. Call when done with the regex instance.

License

MIT License - see LICENSE

Original package by J. Stephen Riley.