Rev Lebaredian <[EMAIL PROTECTED]> wrote:
> >>> | > + my $large_string = eval ' "a" x 5_000_000 ';
>
> I'm not sure of this but it seems to me that the expression will work
> without the eval. I'm guessing the eval is there as form of exception
> handling in case the allocation fails. If this is the case then the
> eval is being used for a well documented and recommended technique.
No. In Perl, each operator, such as 'x', is (at compile time) allocated
a private SV for storing its result. This SV is stored in the
scratchpad of the sub the op is compiled into, and only gets deleted
when the sub is deleted - this is usually at program exit, but happens
earlier with an eval.
Since in this context the eval is purely a way round a pecularity of the
current implementation of perl, its use is probably not be be encouraged.
Dave M.
