I am definitely with AchipA this time: no need to change request.args
carlo
On 23 Mag, 21:32, AchipA <attila.cs...@gmail.com> wrote:
> Hang on, not sure if we're talking about the same thing. Style, as in
> preference of 'if' over 'try' is okay to discuss (although I think
> *forcing* people to use 'if' is wrong). This proposed change, however,
> inherently BREAKS backward compatibility, as seen from my example, for
> anybody using the EAFP approach (myself included). That was my first
> concern. Are we okay with this breakage ?
>
> On May 23, 6:34 pm, mdipierro <mdipie...@cs.depaul.edu> wrote:
>
> > request.args is a special list anyway because it could be made
> > readonly and because its elements can only be non-empty strings. This
> > is why I have difficuly seeing how this will create conflicts.
>
> > I like the fact it would allow to do
>
> > record = db.table[request.args[0]] or redirect(...)
>
> > when you expect a valid record_id in request.args[0]. It is much
> > shorter than
>
> > record = db.table[request.args[0] if request.args else None] or
> > redirect(...)
>
> > which would not work on python 2.4.
>
> > List only breaks checking for existence using try/except but using try/
> > except to determine whether args[i] is a valid argument is not a good
> > programming style in my opinion (although I am as guilty of using it
> > as anybody else).
>
> > Let's wait for more comments anyway.
>
> > Massimo
>
> > On May 23, 11:15 am, AchipA <attila.cs...@gmail.com> wrote:
>
> > > Env and vars are somewhat different, being dicts. The Proper (TM) way
> > > for those would be target = request.vars.get('myoptionalvar', None).
> > > The reason this is the Proper (TM) way is that you *have* to know when
> > > you're handling undefined data (is that a None ? Or a '' ? Maybe 0 ?)
> > > You can't just throw in a None in a middle of a controller and hope it
> > > works out (often trading an IndexError for an even harder to debug
> > > 'unsupported operand type for None'. That would be the PHP way. Easy
> > > on beginners - yes, effect on code quality - terrible. But let's wait
> > > on further comments.
>
> > > On May 23, 5:42 pm, mdipierro <mdipie...@cs.depaul.edu> wrote:
>
> > > > yes but we do this already for request.vars and request.env
>
> > > > anyway, I am not sure about myself about this. Let's here a few
> > > > comments about this can I can revert it.
>
> > > > Massimo
>
> > > > On May 23, 10:29 am, Alexey Nezhdanov <snak...@gmail.com> wrote:
>
> > > > > On Saturday 23 May 2009 18:42:58 AchipA wrote:> Tt does break
> > > > > existing properly written python code (and is very non-
> > > > > > pythonesque).
>
> > > > > +1 except for harshness. Masking exceptions is a BAD THING (TM)
>
> > > > > > Think:
>
> > > > > > try: target = request.args[0]
> > > > > > except:
> > > > > > response.flash = 'No target specified'
> > > > > > return
>
> > > > > > do_something(target)
> > > > > > If this is an issue for people, I think they should improve their
> > > > > > python skills (learn exceptions, for arg in request.args
> > > > > > constructs),
> > > > > > and not fight the language by framework-specific workarounds. They
> > > > > > will benefit from it much more on the long run (as they are bound to
> > > > > > have the same IndexError or KeyError problem anyway, just someplace
> > > > > > else). My 0.02c.
>
> > > > > --
> > > > > Sincerely yours
> > > > > Alexey Nezhdanov
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