--- David Cantrell <[EMAIL PROTECTED]> wrote:
> > >>I wonder how you'd tag a subroutine that can be called as a
> method or
> > >>a regular subroutine.
> > >:horrible_evil_delete_this_entire_file_to_be_safe
> > /me makes notes.
>
> I'm with chromatic on this one. Doing that will make your brain
> hurt.
> Especially if you do it to subroutines/methods that you create on the
> fly with AUTOLOAD. I wish I'd never dunnit.
Yeah, digging through the CGI.pm code base was *real* fun because of
this. Since all functions are, under the hood, methods, then the
beginning of many functions looks like this:
sub param {
my($self,@p) = self_or_default(@_);
...
And what does &self_or_default look like?
sub self_or_default {
return @_ if defined($_[0]) && (!ref($_[0])) &&($_[0] eq 'CGI');
unless (defined($_[0]) &&
(ref($_[0]) eq 'CGI' || UNIVERSAL::isa($_[0],'CGI')) #
slightly optimized for common case
) {
$Q = $CGI::DefaultClass->new unless defined($Q);
unshift(@_,$Q);
}
return wantarray ? @_ : $Q;
}
Lincoln Stein admits that he wouldn't write it this way any more, but
there are plenty of programmers who wouldn't see anything wrong with
this :(
Just for fun, how many potential bugs can you count in the
self_or_default subroutine?
Cheers,
Ovid
--
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