[Python-Dev] Python equivalents in stdlib Was: Include datetime.py in stdlib or not? (original) (raw)

Antoine Pitrou solipsis at pitrou.net
Wed Jul 7 20:42:46 CEST 2010

On Wed, 07 Jul 2010 16:39:38 +0100 Michael Foord <fuzzyman at voidspace.org.uk> wrote:

On 07/07/2010 16:29, Alexander Belopolsky wrote: > [snip...] > >> 4. Does not ctypes make it possible to replace a method of a Python-coded >> class with a faster C version, with something like >> try: >> connect to methods.dll >> check that function xyx exists >> replace Someclass.xyy with ctypes wrapper >> except: pass >> For instance, the SequenceMatcher heuristic was added to speedup the >> matching process that I believe is encapsulated in one O(n**2) or so >> bottleneck method. I believe most everything else is O(n) bookkeeping. >> >> > The ctypes modules is very CPython centric as far as I know. For the > new modules, this may be a valid way to rapidly develop accelerated > versions. For modules that are already written in C, I don't see > much benefit in replacing them with ctypes wrappers.

Nope, both IronPython and PyPy have ctypes implementations and Jython is in the process of "growing" one. Using ctypes for C extensions is the most portable way of providing C extensions for Python (other than providing a pure-Python implementation of course).

Except that ctypes doesn't help provide C extensions at all. It only helps provide wrappers around existing C libraries, which is quite a different thing. Which, in the end, makes the original suggestion meaningless.

Regards

Antoine.

More information about the Python-Dev mailing list