Rsre-wasm NPM | npm.io

RsRe-Wasm

This package is a (currently very minimal) wrapper around the rust crate regex through WebAssembly in JavaScript. The main goal is to provide a safe regex without using node-gyp. You can use it in both Node and the Browser (assuming the platform supports WebAssembly). There's no glue-code for the Browser at the moment.

The naming isn't final as it's confusing.

Example

import { RsReWasm } from 'rsre-wasm';

const regex = new RsReWasm(/(?<year>\d+)-(?<month>\d+)-(?<day>\d+)/g);
const string = "Foo happened on 2020-03-02 and bar happened on 2020-04-10.";
for (const { groups } of string.matchAll(regex)) {
    console.log(groups);
}

// Logs:
//
// { day: "02", month: "03", year: "2020" }
// { day: "10", month: "04", year: "2020" }

Traps

The creation of this Regex is expensive, so you should only instantiate it once:

Bad

for(const input of inputs) {
    // This creates a regex on **every** iteration
    const regex = new RsReWasm(/(?<year>\d+)-(?<month>\d+)-(?<day>\d+)/g);
    if(regex.test(input)) {
        // do something
    }
}

Good

 // Create the regex once, use it multiple times
const regex = new RsReWasm(/(?<year>\d+)-(?<month>\d+)-(?<day>\d+)/g);
for(const input of inputs) {
    if(regex.test(input)) {
        // do something
    }
}