On Thu, 21 Jun 2007 22:33:03 +0100, Tim Bunce wrote:
> On Thu, Jun 21, 2007 at 06:47:11PM +0200, Rafael Garcia-Suarez wrote:
>> On 21/06/07, Steve Hay <[EMAIL PROTECTED]> wrote:
>> >I remember lots of discussion a while ago about constructions like "my
>> >$x = 1 if $y;". I don't remember what the conclusion of it all was,
>> >except that it's probably best avoided. Is that right?
>>
>> Yes, that's right, because that could bypass initialisation of $x if
>> $y is false, leaving the previous value in it, like in state vars.
>
> I thought that issue only related to a "compile-time constant false"
> (such as the one in your example) and not to a runtime expression that
> happened to be false sometimes.
>
> Looking at it another way, are you saying that (ignoring closures)
> subroutine scoped lexicals are not cleared when the subroutine exits,
> but persist (consuming memory) until the subroutine is reentered?
$ ./perl -wle '$q = shift; sub foo { my $x if $q; print $x // $]; \
$x = 42 } foo; $q++; foo' 0
5.009005
42
It looks like it, no?
--
Peter Scott
