On 22 March 2015 at 04:47, Terry Reedy <tjre...@udel.edu> wrote: > On 3/21/2015 12:41 AM, Serhiy Storchaka wrote: >> >> How to document functions with optional positional parameters? >> >> For example binascii.crc32(). It has two positional parameters, one is >> mandatory, and one is optional with default value 0. With Argument >> Clinic its signature is crc32(data, crc=0, /). In the documentation it >> is written as crc32(data[, crc]) (and noted that the default value of >> the second parameter is 0). Both are not valid Python syntax. Can the >> documentation be change to crc32(data, crc=0)? > > > I think the docs should be using / as well.
Right, even though the Python level parser doesn't allow this syntax, it's the one used by Argument Clinic to express positional-only parameters for functions defined in C, and as a result the inspect module uses it as well: >>> import inspect >>> print(inspect.signature(hex)) (number, /) This is the specific problem Larry was aiming to address in https://www.python.org/dev/peps/pep-0457/ - getting the docs, Argument Clinic and the inspect module to align in their notation, even though he wasn't proposing to change Python itself to allow positional-only parameter definitions. Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
