Re: Generic/Variable/Dynamic Subroutines? (Not a redefine)

[haukex]

This will generate those three subs you showed (Update: see Function Templates and Method Names as Strings):

for my $meth (qw/ WriteLine Select Add /) {
    my $sub = sub {
        my $self = shift;
        my $it = $self->OStream->$meth($_[0]);
        $self->Trace(_CallerStr($it));
        return $it;
    };
    no strict 'refs';
    *$meth = $sub;
}

Optionally put that in a BEGIN { ... } block if you want to be able to call the subs without parens.

Here's a simple wrapper class that uses Autoloading, although autoloading can be a bit dangerous and have some caveats (e.g. the following doesn't overload UNIVERSAL methods like can, although it probably should for completeness; Update: also this example always calls the method in scalar context, although that could be changed by inspecting wantarray; plus obviously wrapper and wrapped objects have completely different classes, so isa and especially ref checks would break), so I would recommend the above solution instead. Use this like my $wrapper = Wrapper->new($object); and you should be able to call the original methods from $object on $wrapper instead. Update 2: I guess I should be more clear that the following is really just a demonstration of the (sometimes scary) power of AUTOLOADing and not something I'd recommend for wide use. You might want to look at something like around from Class::Method::Modifiers instead.

package Wrapper;
use Carp;
sub new {
    my ($class,$wrapped) = @_;
    return bless \$wrapped, $class;
}
sub AUTOLOAD {
    my $wrapped = shift;
    (my $meth = our $AUTOLOAD) =~ s/.*:://;
    croak "Wrapped object $$wrapped doesn't have a method $meth"
        unless $$wrapped->can($meth);
    # do stuff here
    my $returnval = $$wrapped->$meth(@_); # call wrapped method
    # and more stuff here
    return $returnval;
}
sub DESTROY {} # don't autoload DESTROY