I want to write an OO module such that the objects will "carry" user-supplied subs. Now I want these subs to be allowed to give error and warning messages based on info stored in the objects themselves, so that they will have to "communicate" in some way or the other with them.

The most logical solution that occurred to me would be of passing the object itself as a first argument to the called sub (this would be part of the UI of the module), so that the latter could call a suitable method on it.

Any alternative suggestion? How is this kind of things generally done?

An oversimplified, and somewhat ridicoulous, but hopefully illustrative example of what I meant above is as follows: 

#!/usr/bin/perl

use strict;
use warnings;

package Foo::Parse;

sub new {
    my ($self, $name, $action)=@_;
    bless { _name => $name,
            _action => $action }, $self;
}

sub parse {
    my $self=shift;
    $self->{_action}->($self, @_);
}

sub warn {
    my ($self,@msg)=@_;
    warn "[$self->{_name}] @msg\n";
}

package main;

my $fp=Foo::Parse->new( 'FooParser',
    sub {
        my $self=shift;
        local $_=shift;
        s/^\w+:// or
          $self->warn("something wrong!");
        split /,/;
    } );

$fp->parse($_) while <>;

__END__

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In reply to Seeking advice for OO-related strategy by blazar

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