OK, thanks for the comments, everyone. I'm glad to hear that people generally think this is a useful idea. Some specific replies: On Tue, Feb 16, 2016 at 4:22 AM, Chris Angelico wrote:

For what it's worth, I read your post with interest, but didn't have anything substantive to reply - mainly because I don't use regexes much. But it would be rather cool to be able to decompile a regex. Imagine a regex pretty-printer: compile an arbitrary string, and if it's a valid regex, decompile it to a valid source code form, using re.VERBOSE. That could help _hugely_ with debugging, if the trick can be pulled off.

ChrisA

That's exactly the type of tools I envision being made available by third parties. Depending on how much I get invested into this project, I may even write such a tool myself (though that's not guaranteed). On Tue, Feb 16, 2016 at 4:55 AM, Paul Moore wrote:

Sorry. I don't personally have any issue with the proposal, and it sounds like a reasonable idea. I don't think it's likely to be *hugely* controversial - although it will likely need a little care in documenting the feature to ensure that we are clear that there's no guarantees of backward compatibility that we don't want to commit to on the newly - exposed data. And we should also ensure that by exposing this information, we don't preclude changes such as the incorporation of the regex module (I don't know if the regex module has a bytecode implementation like the re module does).

The regex implementation is indeed something I would need to investigate here, and will do so before I go too far.

The next step is probably simply to raise a tracker issue for this. I know you said you have little C experience, but the big problem is that it's unlikely that any of the core devs with C experience will have the time or motivation to code up your idea. So without a working patch, and someone willing and able to respond to comments on the patch, it's not likely to progress.

Tracker issue is already filed: http://bugs.python.org/issue26336 I actually filed the issue before I realized that the mailing lists were a better place to discuss it.

But if you are willing to dig into Python's C API yourself (and it sounds like you are) there are definitely people who will help you. You might want to join the core mentorship list (see http://pythonmentors.com/) where you should get plenty of assistance. This proposal sounds like a great "beginner" task, as well - so even if you don't want to implement it yourself, still put it on the tracker, and mark it as an "easy" change, and maybe some other newcomer who wants a task to help them learn the C API will pick it up.

I'll look into the mentorship list; thanks for the link. As for marking it "easy", I don't seem to have the necessary permissions to change the Keywords field; perhaps you or someone else can set that flag for me? If so, I'd appreciate it. :-)

Hope that helps - thanks for the suggestion and sorry if it seems like no-one was interested at first. It's an unfortunate fact of life around here that things *do* take time to get people's interest. You mention patience in one of your messages - that's definitely something you'll need to cultivate, I'm afraid... :-)

Patience is something I've been working on since I was a little kid. I'm 29 years old now, and it still eludes me from time to time. But yes, it's something I'll have to work on. :-P Also, I received a small patch off-list from Petr Viktorin implementing a getter for the code list (thanks, Petr). I'll need to test it, but from the little I know of the C API it looks like it will get me started in the right direction. Assuming that works, what's left is a public constructor for the regex type (to enable optimizers), a dis-like module, and docs and tests. I don't think this would be major enough to require a PEP, but of course being new here, I'm open to being told I'm wrong. :-)