Question: Is there a code editor that offers advanced features like RegEx previewing, snippet running, and library generation?

If you're looking for a full-featured code editor with lots of bells and whistles, CodeMenu is a great option. This snippets manager for macOS has syntax highlighting, HTML and RegEx previewing, snippet execution, library generation and support for many programming languages. It also has a RegEx tester, converter and generator. CodeMenu has its own Snippets Store to search and share snippets, and it can use AI to generate descriptions and titles.

Another good option is Zed, a high-performance, multiplayer code editor that tries to offer the power of an IDE but with the snappiness of a lightweight editor. Zed features AI-assisted code generation, an integrated terminal, Vim mode, customizable themes and support for language servers like Rust and TypeScript. It also has advanced collaboration abilities, so it's good for team programming.

If you're a regex power user, rgx.tools is an AI-powered regex generator and editor that uses GPT-3.5 Turbo to generate regex patterns from text prompts. The tool can be used to generate regex for common tasks like date and phone number validation, and it's free to use, so it's a great resource for anyone who uses regular expressions a lot.

And then there's GitHub Copilot, which offers AI help in many aspects of your development work. It offers code completion, translates natural language prompts into code completions and offers chat help to ask questions about codebases. GitHub Copilot can be integrated with other tools and services and works with many IDEs and terminals so developers can get help without slowing down or compromising security.