Hi folk:

I'm fairly new to Moose & I cannot seem to figure out this problem: I have a string attribute to which I wish to prepend another string... I try with builder: no luck; I tried w BUILDARGS which works when an instance is initiated, but not when I try to change the attribute...

My testing module: 

package Test;
use Moose;

my $prepend = '/some_string/';
has 'fname' => (is => 'rw',
              isa => 'Str');

has 'appended'      => ( is => 'rw',
                      isa => 'Str',
                        #  lazy => 1,
                        #builder => 'set_appended'
                        );
1;

sub BUILDARGS {
    my $class = shift;
    my %args = ref $_[0] ?  %{$_[0]} : @_;
    $args{appended} =  $prepend . $args{appended} if exists $args{appe
+nded};
    return \%args;
}

sub set_appended {
    my $self = shift;
    my $value = $self->appended;
    return $prepend . $value;
}

[download]

My test program 


use 5.010;
use strict;
use warnings;

use lib ".";
use Test;
    
my $t  = new Test( fname    => "fred",
                   appended => "this_is_appended_string");

say $t->fname;
say $t->appended;
$t->appended ('another_string');
say $t->appended;

[download]

The output 

fred
/some_string/this_is_appended_string
another_string

[download]

Thx in advance..

In reply to Prepend a Moose attribute when changed by FryingFinn

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