A Visualizer, Debugger and Editor for C# Regex

[longxya]

ADDRESS:

GitHub
regexdev

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Basic demonstration

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C#'s regex engine is extremely powerful, especially with advanced features like balancing groups. However, most existing regex tools don't support C#-specific features.

I built regexdev to visualize and debug C#-style regex with full support for advanced features like balancing groups.

Key Features:

• AST-based regex visualization
• Step-by-step matching and debugging
• Interactive regex editing
• Breakpoints during matching
• Multi-view / multi-panel inspection

Verification of Correctness:

To ensure the accuracy of the matching process, regexdev continuously compares the results against the official C# regex engine:

• Match count comparison
• Index and Length of all captures in every Group

If any discrepancies are detected, the tool immediately reports it.

At the moment, only the regex parser is open-source, which has been rewritten with a clean AST-based design for better visualization and extensibility. The full debugger are still being refactored and are not open-sourced yet.

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Especially:

I wrote a C# regex parser to replace the lexer and handle most grammar checks.

I didn’t want to write a lexical analyzer.

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Feedback, suggestions, and discussions are very welcome!

[longxya]

An interactive console demo is provided for experimenting with the regex parser.

Input a regex expression, then type parse on a new line and press Enter
to visualize the parsed AST in textual form.