Re: [Python-Dev] a Python interface for the AST (WAS: DRAFT: python-dev...)
On 11/23/05, Greg Ewing [EMAIL PROTECTED] wrote: Brett Cannon wrote: There are two problems to this topic; how to get the AST structs into Python objects and how to allow Python code to modify the AST before bytecode emission I'm astounded to hear that the AST isn't made from Python objects in the first place. Is there a particular reason it wasn't done that way? I honestly don't know, Greg. All of the structs are generated by Parser/asdl_c.py which reads in the AST definition from Parser/Python.asdl . The code that is used to allocate and initialize the structs is in Python/Python-ast.c and is also auto-generated by Parser/asdl_c.py . I am guessing here, but it might have to do with type safety. Some nodes can be different kinds of subnodes (like the stmt node) and thus are created using a single struct and a bunch unions internally. So there is some added security that stuff is being done correctly. Otherwise memory is the only other reason I can think of. Or Jeremy just didn't think of doing it that way when this was all started years ago. =) But since it is all auto-generated it should be doable to make them Python objects. -Brett ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
[Python-Dev] a Python interface for the AST (WAS: DRAFT: python-dev...)
I wrote (in the summary): While there is no interface to the AST yet, one is intended for the not-so-distant future. Simon Burton wrote: who is doing this ? I am mad keen to get this happening. Brett Cannon wrote: No one yet. Some ideas have been tossed around (read the thread for details), but no one has sat down to hammer out the details. Might happen at PyCon. Simon Burton wrote: Yes, i've been reading the threads but I don't see anything about a python interface. Why I'm asking is because I could probably convince my employer to let me (or an intern) work on it. And pycon is not until febuary. I am likely to start hacking on this before then. Basically, all I saw was your post asking for a Python interface[1], and a few not yet responses. I suspect that if you were to volunteer to head up the work on the Python interface, no one would be likely to stop you. ;-) [1]http://mail.python.org/pipermail/python-dev/2005-October/057611.html Steve -- You can wordify anything if you just verb it. --- Bucky Katt, Get Fuzzy ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] a Python interface for the AST (WAS: DRAFT: python-dev...)
On 11/22/05, Brett Cannon [EMAIL PROTECTED] wrote: But if I had my way I think that having all AST objects be PyObjects and then providing support for all three ways of getting access to the AST (command-line, sys iterable, function for specific code object) would be fantastic. There needs to be a function that takes a filename (or string of code) and returns an AST. Hmm, it would be nice to give a function a module name (like from an import statement) and have Python resolve it using the normal sys.path iteration. n ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] a Python interface for the AST (WAS: DRAFT: python-dev...)
On 11/22/05, Neal Norwitz [EMAIL PROTECTED] wrote: On 11/22/05, Brett Cannon [EMAIL PROTECTED] wrote: But if I had my way I think that having all AST objects be PyObjects and then providing support for all three ways of getting access to the AST (command-line, sys iterable, function for specific code object) would be fantastic. There needs to be a function that takes a filename (or string of code) and returns an AST. Yes and I guess. =) I can see the filename to check a module useful for stuff like PyChecker. But for a string of code, I don't think it would be that critical; if you provide a way to get the AST for a code object you can just pass the string to compile() and then get the AST from there. Hmm, it would be nice to give a function a module name (like from an import statement) and have Python resolve it using the normal sys.path iteration. Yep, import path - filename path would be cool. -Brett ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
Re: [Python-Dev] a Python interface for the AST (WAS: DRAFT: python-dev...)
At 06:32 PM 11/22/2005 -0800, Brett Cannon wrote: Hmm, it would be nice to give a function a module name (like from an import statement) and have Python resolve it using the normal sys.path iteration. Yep, import path - filename path would be cool. Zipped and frozen modules don't have filename paths, so I'd personally rather see fewer stdlib modules making the assumption that modules are files. Instead, extensions to the PEP 302 loader protocol should be used to support introspection, assuming there aren't already equivalent capabilities available. For example, PEP 302 allows a 'get_source()' method on loaders, and I believe the zipimport loader supports that. (I don't know about frozen modules.) The main barrier to this being really usable is the absence of loader objects for the built-in import process. This was proposed by PEP 302, but never actually implemented, probably due to time constraints on the Python 2.3 release schedule. It's relatively easy to implement this missing loader class in Python, though, and in fact the PEP 302 regression test in the stdlib does exactly that. Some work, however, would be required to port this to C and expose it from an appropriate module (imp?). ___ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
