[Python-Dev] PEP 362: 4th edition

[Nick Coghlan]

On Mon, Jun 18, 2012 at 5:08 PM, Jim Jewett <jimjjewett at gmail.com> wrote:
> But perhaps they *should* know their relative position.

No, relative position is a property of the Signature - a parameter has
no position until it is made part of a signature.

> Also,
> positional_only, *args, and **kwargs should be able to remove name
> from the list of compared attributes.

As you yourself said, removing the name from consideration for
positional arguments is potentially dangerous - a function that
accepts (source, dest) is very different from one that accepts (dest,
source). If you don't care about names, then call bind() to see if it
works or write your own more permissive comparison operation. If you
do care about names, then the default equality definition is
appropriate.

Ultimately, people are going to be free to do their own thing. The
heart of the new API is to get all of this already available
information out into a more conveniently manipulable format. Once we
see what people do with it, *then* it is time to discuss additional
convenience APIs (such as Signature level properties for parameter
subsets).

Don't overengineer it at the foundational level - let people build
their own additional layers of customisation on top.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia