vscode-oniguruma

What is vscode-oniguruma?

The vscode-oniguruma package is a Node.js binding to the Oniguruma regular expressions library. It is primarily used in Visual Studio Code to power the textmate tokenizer, which is responsible for syntax highlighting based on TextMate grammars. The package allows for efficient regular expression matching and is optimized for use in text editors.

What are vscode-oniguruma's main functionalities?

Regular Expression Matching

This feature allows you to match strings against regular expressions. The code sample demonstrates how to load the Oniguruma WebAssembly binary, create a new OnigScanner with a regular expression, and find the next match in a given string starting from a specific position.

const { loadWASM, OnigScanner } = require('vscode-oniguruma');

// Load the WebAssembly binary for Oniguruma.
loadWASM(require('vscode-oniguruma/release/onig.wasm')).then(() => {
  const scanner = new OnigScanner(['\\w+']);
  const match = scanner.findNextMatchSync('hello world', 0);
  console.log(match);
});

Syntax Highlighting

This feature is used for syntax highlighting by matching keywords or patterns in a source code string. The code sample shows how to create an OnigScanner with a pattern for matching 'if' or 'else' keywords, create an OnigString from source code, and then find and log the matched keyword.

const { OnigScanner, OnigString } = require('vscode-oniguruma');

const scanner = new OnigScanner(['\\b(if|else)\\b']);
const source = new OnigString('if (condition) { return true; } else { return false; }');

const match = scanner.findNextMatchSync(source, 0);
if (match) {
  console.log(`Matched keyword: ${source.content.substring(match.captureIndices[0].start, match.captureIndices[0].end)}`);
}

Other packages similar to vscode-oniguruma

xregexp

XRegExp is an npm package that provides augmented, extensible regular expressions. It includes additional syntax and flags and offers features like named capture groups and format strings. While it does not use WebAssembly and is not specifically optimized for syntax highlighting in editors, it is a powerful tool for complex regular expression operations in JavaScript.

re2

RE2 is a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python. It is built on the RE2 C++ library and prevents catastrophic backtracking by design. Unlike vscode-oniguruma, RE2 focuses on performance and safety in regular expression matching rather than syntax highlighting.

README

vscode-oniguruma

access oniguruma api from packaged with vscode