Regulex

What Regulex is

Regulex is a JavaScript regular expression parser and visualizer for JavaScript/ECMAScript patterns. Enter a pattern on its web page and choose Visualize to see a graph of how the expression is structured. The page also has IgnoreCase, Multiline, and GlobalMatch options, an Error Message area for syntax problems, and controls to export the graph as an image or embed it on another site with an HTML iframe. Detailed syntax errors can often point to the position of a problem in a pattern.

The project is written in pure JavaScript and requires no backend. Developers can install it with `npm install regulex` and use its parse and visualize APIs in Node.js. A browser bundle named `dist/regulex.js` can be built from the legacy branch, as documented by the project. Regulex is open source and free. Its documented limits include no support for octal escapes; decimal escapes are treated as back references. It does not offer plain-language pattern explanations, step-through debugging, code generation, or saved patterns. The repository describes the project as under reconstruction.

Who it suits

Regulex suits JavaScript developers who want to inspect a regular expression as a graph, diagnose syntax errors, or use parsing and visualization APIs in Node.js. It can also suit someone who wants to export or embed a pattern visualization from the web page.

Limits

Regulex does not support octal escapes and treats decimal escapes as back references. The repository describes the project as under reconstruction.

Getting started

1. Open https://jex.im/regulex/ in a web browser.
2. Enter a JavaScript regular expression and choose Visualize.
3. Set IgnoreCase, Multiline, or GlobalMatch as needed.
4. Use Export Image to save the graph, or the embed control to place it on another site.
5. For Node.js use, install the package with `npm install regulex` and use its parse and visualize APIs.

Verdict

Choose Regulex to visualize JavaScript regular expressions in a browser or use its documented APIs in Node.js. Its graph export and embed controls are useful when you need to share a visualization. Look elsewhere if you need pattern explanations, match stepping, code generation, saved patterns, or octal escape support.