On Dec 31, 2007 5:43 PM, gst <[EMAIL PROTECTED]> wrote:
> hi,
>
> iirc, in C if I store somwhere a pointer to a "stack" value (e.g.:
> call a function with an auto variable, return its pointer) i know i'm
> going to mess things, since that piece of data will be most probably
> overwritten by subsequent calls.
>
> if I do the same in Perl (with a hard ref), do I have any guarantee
> that the same behavior (implicit aliasing) does - or does not (every
> new scalar is guaranteed to not alias the old non existant value) -
> apply?
>
> thank you in advance
> gst
When you say
my @refs;
for (1 .. 5) {
my $value;
push @refs, \$value;
}
You get five distinct memory locations. Each time the my function is
executed you get a new memory address. This is why things like
closures work. Saying my in Perl is like* saying
struct scalar_struct* var = malloc(sizeof(struct scalar_struct));
with the call to free() being handled for by the garbage collection
system (when the number of references goes to zero).
* this is not literal
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