Further Adventures of the Debugger

Harry Pierson (Microsoft IronPython PM) has been experimenting with writing an IronPython debugger (ipydbg) on top of the .NET MDbg APIs.

When we last left him, he had implemented Just My Code (JMC) support allowing you to step into IronPython code. Since then he has made a lot of progress including a colourful REPL (interactive console) and solving some difficult problems around getting to real values behind boxed IronPython variables (needed for showing local variables). He has blogged extensively on what he has been up to (more recent posts last):

• Showing Source Code
  
• Colorful Console
• IronPython ConsoleColorMgr (the colorful console code pulled out into a separate IronPython module)
  
• A Little Hack...err...Cleanup
  
• Getting Local Variables
• Displaying Values
• Command Routing
• Getting Arguments
• REPL Console

A lot of functionality is now present. In the command routing entry Harry outlines the seven commands supported by the debugger so far: Continue, Quit, Show Stack Trace, Show Locals, Step Over, Step In, and Step Out. The next step:

While having a debugger REPL is really convenient for prototyping new ipydbg commands, it’ll really shine once I get function evaluation working. Then I’ll be able to open a REPL console where the commands are executed in the target process instead of the debugger process as they are now. That will be very cool. Until then, the latest code is – as always – up on GitHub.

On the subject of downloading the source code for the ipydbg project, Harry has another blog entry outlining all of his tinkerings and code that he has made available. This includes codedom.py, ipypulldom.py, and xml2py.py - all under the MS-PL open source license:

• devhawk_ipy