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Re: 'around' method modifier does not seem to work

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From:
Chris Prather
Date:
August 7, 2015 16:27
Subject:
Re: 'around' method modifier does not seem to work
Message ID:
1438964863928.d6f7c45f@Nodemailer
So you'll need to provide a reduced example that demonstrates the behavior your showing. When I tried to reproduce (with the script below) the attribute was being set just fine.




#!/usr/bin/env perl

use 5.12.1;

use warnings;




{




    package AroundTest;

    use Moose;




    has foo => ( is => 'rw' );

    around foo => sub {

        my ( $next, $self, $seq ) = @_;

        $seq = uc($seq);

        $self->$next($seq);

    };

}




my $at = AroundTest->new();

$at->foo('bar');

say $at->dump;

On Thu, Aug 6, 2015 at 7:04 PM, Marcos Barbeitos <msbarbeitos@gmail.com>
wrote:

> Howdy,
> I looked up the behavior of the modifier 'around' in <
> http://search.cpan.org/~ether/Moose-2.1600/lib/Moose/Manual/MethodModifiers.pod#Around_modifiers>,
> and the code snipet is:
>   around 'size' => sub {
>       my $orig = shift;
>       my $self = shift;
>       return $self->$orig()
>           unless @_;
>       my $size = shift;
>       $size = $size / 2
>           if $self->likes_small_things();
>       return $self->$orig($size);
>   };
> In my code, I have:
> has 'sequence' =>
> (
>     is => 'rw'
>   , isa => 'Str'
>   , predicate => 'has_sequence'
> );
> around 'sequence' => sub
> {
>     my $orig = shift;
>     my $self = shift;
>     my $sequence = uc shift;
>     # Do lots of things with $sequence and then
>     return $self->$orig( $sequence );
> }
> But the attribute is not set.
> I've tried lots of variations of the last line:
> $self->$orig( $sequence );
> return $orig->( $self, $sequence );
> $orig->( $self, $sequence );
> return $sequence;
> With no success, as expected. However, if I do:
> around 'sequence' => sub
> {
>     my $orig = shift;
>     my $self = shift;
>     return $self->$orig( @_ );
> }
> The attribute is set and life goes on. Of course, that does not work for me
> because I need to do a bunch of things to the argument passed to this
> method.
> Any ideas about the reasons for the (apparent?) discrepancy in behavior?
> Best wishes and thanks in advance.
> --
> Marcos S. Barbeitos
> Departamento de Zoologia - Sala 360
> Setor de Ciências Biológicas
> Universidade Federal do Paraná
> Caixa Postal 19020
> Curitiba, PR 81531-990
> Brazil
> Phone: (55 41) 3361-1634
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