[Python-3000] enhanced descriptors, part 2

[tomer filiba]

>      f.position      -- used to access the current position
>      f.position = x  -- seek to an absolute position (may be relative to end)
>      f.seek_by(x)    -- seek by a relative amount
>
> Properties are nice, but there's nothing wrong with methods either. If
> we went with the second approach, people might foolishly use
> "f.position += 4" where they intended "f.seek_by(x)" and it would still
> work fine, it just wouldn't be optimized. That's really not so bad.

okay, i'm fine with that. but i'm not happy with the fact it's not *possible*
to implement such things in python. perhaps with time more use-cases
will show it's needed. until then... ;)


-tomer

On 6/13/06, Michael Chermside <mcherm at mcherm.com> wrote:
> tomer writes:
> > there really is a need for "enhanced descriptors", or something like
> > that. i'm having serious trouble implementing the position property,
> > as python is currently limited in this area.
>
> No, this doesn't necessarily imply that we need "enhanced descriptors",
> an alternative solution is to change the intended API for file
> positions. After all, the original motivation for using a property
> was that it was (a) nice to use, (b) easy to read, and (c) possible to
> implement. If (c) isn't true then perhaps we rethink the API.
>
> After all, how bad would it be to use the following:
>
>      f.position    -- used to access the current position
>      f.seek_to(x)  -- seek to an absolute position (may be relative to end)
>      f.seek_by(x)  -- seek by a relative amount
>
> Or even go half-way:
>
>      f.position      -- used to access the current position
>      f.position = x  -- seek to an absolute position (may be relative to end)
>      f.seek_by(x)    -- seek by a relative amount
>
> Properties are nice, but there's nothing wrong with methods either. If
> we went with the second approach, people might foolishly use
> "f.position += 4" where they intended "f.seek_by(x)" and it would still
> work fine, it just wouldn't be optimized. That's really not so bad.
>
> -- Michael Chermside
>
>