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Date: Tue, 11 Dec 2007 22:33:57 -0600
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To: Ken Stanley <dohpaz@gmail.com>
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Subject: Re: [PHP-DEV] namespace improvements to be committed very soon -
 final review
From: greg@chiaraquartet.net (Gregory Beaver)

Ken Stanley wrote:
>
>
> On Dec 11, 2007 6:13 PM, Gregory Beaver <greg@chiaraquartet.net
> <mailto:greg@chiaraquartet.net>> wrote:
>
>     The example above shows that imported names are reset at each
>     namespace
>     declaration.  There is no prohibition on this code:
>
>     <?php
>     namespace one; {
>     use Blah::A;
>     // code
>     }
>     namespace two; {
>     use Foo::A;
>     // code
>     }
>     ?>
>
>     Users who wish to use brackets may do so.  The performance penalty
>     imposed by using brackets is minor for some cases, and for users
>     who are
>     following the recommended practice of 1 namespace per file, the
>     syntax
>     is ideal. 
>
> My question is that if using the above code already incurs a perf
> penalty, then why not just go ahead and include true support for
> braces in namespaces. Unless there is an additional penalty that I'm
> missing, the only difference between true braces and the above is that
> the above looks like a cheap hack (note: the use the of phrase "cheap
> hack" is in no way meant to demean the hard work of the people
> involved with the namespace implementation, and is the sole opinion of
> the poster :)).
Because the performance penalty is unnecessary, just use 1 namespace per
file for your code.  Those who need to combine files are not doing it
for maintenance reasons.

Just to be clear, this code does *not* have a performance penalty:

<?php
namespace one;
use Blah::A;
//code
namespace two;
use Foo::A;
// code
?>

Any brackets adds another set of shift/reduce to the parser, regardless
of how the syntax of the language is defined.

Greg