I just started playing around with Moose (or actually Mouse). I'm a little confused about the purpose of the "builder" functions and the "after" methods...it seems that an object's other attributes are not accessible within them: 
#!/usr/bin/perl -w
use strict;

package Test;
use Mouse;
use YAML::XS;

has 'n' => (is => 'rw', isa => 'Int', builder => 'do_n');
has 'n2' => (is => 'rw', isa => 'Int');

after do_n => \&do_n2;

sub do_n {
    my $s = shift;
    print "In do_n() \$s = $s\n";
    return 3;
}

sub do_n2 {
    my $s = shift;
    print "In do_n2() \$s = $s\n";
# any reference to $s->{'n'} here results in uninitialized value...
    print Dump $s;
}

__PACKAGE__->meta->make_immutable();

package main;
my $test = Test->new();

[download]
So do_n(), the builder function, fires, then do_n2() fires "after". However, while do_n2() is provided with the object instance this instance does not contain the value for n which was initialized by the builder. I suppose I could just take care of that kind of thing in a "BUILD" function but am curious as to what I have misunderstood about the Moose/Mouse object construction.

In reply to Simple Mouse/Moose question by halfcountplus

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