On Jan 28, 2011, at 6:05 AM, DenesL wrote:
>
> On Jan 27, 5:58 pm, Jonathan Lundell <[email protected]> wrote:
>> On Jan 27, 2011, at 12:48 PM, DenesL wrote:
>>
>> Still, it bothers me that arg1 == arg1/ != arg1//; <ignore exactly one
>> (optional) trailing slash> seems like an odd rule.
>>
>> Notice also that '/'.join(['arg1', '']) is 'arg1/', not 'arg1//'.
>
> True.
> Moreover URL('f',args=['arg1','']) is
> /app/ctl/f/arg1/
>
> maybe that should be considered a bug as it should be
> /app/ctl/f/arg1//
It's no so obviously a bug.
URL('f',args=['arg1','arg2']) is /app/ctl/f/arg1/arg2 or
/app/ctl/f/'arg1'/'arg2' (quotes added for clarity)
so suppose arg2 is ''; the consistent transformation is:
URL('f',args=['arg1','']) -> /app/ctl/f/'arg1'/'' or /app/ctl/f/arg1/ without
the quotes
I see three defensible choices. In all cases, .../arg1 -> ['arg1']
1. .../arg1/ -> ['arg1', ''] .../arg1// -> ['arg1', '', '']
2. .../arg1/ -> ['arg1'] .../arg1// -> ['arg1', '']
3. .../arg1/ -> ['arg1'] .../arg1// -> ['arg1']
#1 follows Python split/join. Each trailing slash is another empty-string arg.
#2 adds a trailing slash on output iff the last arg is '', and always deletes
one trailing slash on input if it's present.
#3 ignores all trailing slashes (that's the current code)
#1 is the most simple, consistent and elegant, it seems to me. Its drawback is
that we sort of expect that .../arg1 and .../arg1/ are the same URL. But that's
not always the case, and I don't see a big problem with saying that a visible
difference has consequences. Also, we're mostly generating our own URLs, so we
control what they look like; they're not often being typed.
#2 follows the expectation that .../arg1 and .../arg1/ are the same, but it
does so at the expense of treating '' differently from all other arg values.
#3 takes a different approach, flatly declaring that trailing slashes are never
significant. The downside is that trailing empty args ('') cannot be made
explicit in the URL (though in fairness, in current web2py they're illegal,
so...).
We should get this resolved before Massimo releases the next stable version.
Massimo, do you have a preference? I'm leaning toward #1 at the moment, but not
very strongly.
>
> since URL('f',args=['arg1','','arg3'] is
> /app/ctl/f/arg1//arg3
>
> which is correct.
