[Catalyst] TT2 + CP::Authentication + DBIC gotcha

[Matt S Trout]

On Fri, Jul 13, 2007 at 05:31:53PM +0100, Matt Lawrence wrote:
> stephen joseph butler wrote:
> >On 7/13/07, Matt Lawrence <matt.lawrence at ymogen.net> wrote:
> >>Perrin Harkins wrote:
> >>> my $vote = $foo if ($bar);  # <--- bad!
> >>>
> >>What's wrong with that? I find it a lot more readable than
> >>
> >>my $vote;
> >>if ($bar) {
> >>    $vote = $foo;
> >>}
> >
> >It doesn't work this way, but suppose you wrote this:
> >
> >if ($bar) {
> > my $vote = $foo
> >}
> >
> >Now see why it's wrong? The way you wrote it is kind of ambiguous for
> >the way we think of postfix operators. If you want something one line,
> >how about this:
> >
> >my $vote = $foo ? $bar : undef;
> 
> I can't replicate this behaviour. As far as I can tell, the postfix if 
> is identical to the block if I wrote above.
> 
> 
> perl -Mstrict -wle 'my $foo = 1 if 0; print defined $foo ? $foo : "undef"'
> undef
> 
> 
> Has the bug been fixed?

No, because people use the "if 0" construct as a way to create a static.

cain$ re.pl 
$ sub foo { my $foo if 0; $foo++; }                                             
$ foo();                                                                        
0                                                                               $ foo();
1                                                                               $ foo();
2                                                                               $ 

However in 5.10 you -will- get a warning using this construct since it almost
always indicates buggy code; the number of people who actually -need- a
static rather than just a lexically closed-over var is vanishingly small and
they can explicitly turn off the behaviour themselves.

-- 
      Matt S Trout       Need help with your Catalyst or DBIx::Class project?
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