Other situations like this (was RE: [Python-Dev] Nested scopes resolution -- you can breathe again!)

[Thomas Wouters]

On Fri, Feb 23, 2001 at 06:30:32PM -0500, Jeremy Hylton wrote:
> >>>>> "TW" == Thomas Wouters <thomas@xs4all.net> writes:
>   TW> On Fri, Feb 23, 2001 at 06:00:59PM -0500, Jeremy Hylton wrote:
>   >> Hmmmm...  I'm not yet sure how to deduce indent level 0 inside
>   >> the parser.

>   TW> Uhm, why are we adding that restriction anyway, if it's hard for
>   TW> the parser/compiler to detect it ? I think I'd like to put them
>   TW> in try/except or if/else clauses, for fully portable code. 

> If it were allowed inside an if/else statement, the compiler, it would
> become something more like a runtime flag.  It sounds like you want the
> feature to be enabled only if the import is actually executed.  But that
> can't work for compile-time directives, because the code has got to be
> compiled before we find out if the statement is executed.

Right, I don't really want them in if/else blocks, you're right. Try/except
would be nice, though.

>   TW>                                                            While
>   TW> on the subject, a way to distinguish between '__future__ not
>   TW> found' and '__future__.feature not found', other than hardcoding
>   TW> the minimal version might be nice.

> There will definitely be a difference!

> Presumably all versions of Python after and including 2.1 will know
> about __future__.  In those cases, the compiler will complain if
> feature is no defined.  The complaint can be fairly specific:
> "__future__ feature curly_braces is not defined."

Will this be a warning, or an error/exception ?

Must-stop-working-sleep-is-calling-ly y'rs, ;)

-- 
Thomas Wouters <thomas@xs4all.net>

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