Front page | perl.perl5.porters |
Postings from March 2008
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
G'day wonderful p5pers,
With Perl 5.10 released and the ability to write lexical pragmata easily,
I've started scratching a long-standing itch of mine, that of Fatal.pm
having package-wide scope.
The result is current a proof-of-concept called 'lethal'[1], which exists as
a separate module that uses Fatal to do the heavy lifting. The results look
like this:
use lethal qw(open close);
open(my $fh, '<', 'some_file); # Dies on error.
{
no lethal 'open';
open(my $fh2, '<', 'other_file'); # Fails silently.
close($fh); # Dies on error.
no lethal;
close($fh2); # Fails silently.
}
close($fh3); # Dies on error.
I'm happy releasing this as a stand-alone module, but I've had more than one
suggestion that this should be integrated into Perl's core Fatal module,
perhaps with a syntax like:
use Fatal qw(:lexical open close chdir);
no Fatal qw(:lexical open);
no Fatal qw(close); # Lexical assumed
Modifying Fatal means that potentially everyone with Perl 5.10.1 can have
the lexical behaviour (or 5.10.0+CPAN if we dual-life Fatal), which I hope
is a fairly intuitive leap from what we have now. It also makes my code a
little easier,
On the other hand, I see adding a :lexical option to Fatal as a potential
source of bugs. It's easy to leave out by accident (resulting in
package-wide changes), the upper-case letter means it doesn't look like it
has lexical scope (although the :lexical says otherwise), and it's easy to
feel that it should be backwards compatible when it's not. "use lethal"
avoids these problems.
It's at this point where I need your help; in particular your feedback and
thoughts. Should I be aiming to modify Fatal? Should this be released as a
stand-alone module? Is there anything special I should be aware of when
thinking to suggest changes to any of Perl's core modules?
For reference, there's also been some discussion about this on Perlmonks
<http://perlmonks.org/?node_id=673060> and modules@perl.org
<http://www.xray.mpe.mpg.de/mailing-lists/modules/2008-03/msg00138.html>.
Many thanks in advance,
Paul
[1] Originally I was toying with the names 'fatal', 'lexfatal', and
'exceptions'. Thanks to BrowserUk @ PerlMonks for the name 'lethal'.
- --
Paul Fenwick <pjf@perltraining.com.au> | http://perltraining.com.au/
Director of Training | Ph: +61 3 9354 6001
Perl Training Australia | Fax: +61 3 9354 2681
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (MingW32)
iD8DBQFH0/Uyx5N6j7FHnlURAtRHAJ9ZK2/a+t2TrTFA6jkoHjyM9WophgCfRuN9
XiM0KLKiHHoA+ddOLCIwVvA=
=qYv9
-----END PGP SIGNATURE-----
Thread Next