I'm planning a little module ( an interactive cli using Term::ReadLine ) but I want make possible for the module user to add some method in the constructor, no Moo* usage is planned so I'd like to see basic perl approaches. At the moment I have soemthing like:

sub new{
        my $class = shift;    
        my %opts = @_;    
        unless ( defined $opts{dumper} ){
                require Data::Dumper;
                # + () to avoid Name "Data::Dumper::Dumper" used only 
+once: possible typo at
                # full qualified name to avoid runtime error
                $opts{dumper} = sub{ print +Data::Dumper::Dumper(\$_[0
+]) }        
        }
        return bless { %opts }, $class;       
}
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dynamic method creation

I can build up a method dynamically with *{"${class}::${meth}"} = sub { my $self = shift; ... } I imagine I can do this directly in the new constructor, right? There are drawbacks or pitfall I overlooked in this approach?

dispatch table

The above code for new adds not a method but a property of the object actually being a callable sub: after I can access it like in  $obj->{dumper}->([1,2,{a=>42}])

I can expand this providing to the module user a method to add commends: use Data::Dump; $obj->add_command( {descr=>'a dumper', command => sub{ dd $_[0] } )

This seems to me a simpler approach and I cant imagine drawbacks using it. The only one I can imagine is that not being a method I cannot have $self available inside this calls (even if I dont know atm if will be needed).

pseudo methods?

But I can craft execute_command to pass $self as first argument:

sub execute_command{
   my $self = shift;
   my $wanted_command = shift;
   my @whole_data = @_;
   
   $self->{ $wanted_command }->( $self, @whole_data );
}
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This leads to something like a pseudo method; is this too dirty? Has other drawbacks? Do you expulse me from perlmonks if I write it down? :)

In addition: if new will be as above in the final module, should I add Data::Dumper to prerequisites? I'd say yes but... if not Data::Dumper but Math::Mersenne::Primes was the case? I must add it to prerequisites even if there is the chance it will be never loaded?

L*