I learned something about pack/unpack writing Updated QuickTime format movie file dumper. But the cool thing I learned writing that code was using can to assist in the context of a "dispatch by name":

        my $member = "dump_$key";
        my $name = "name_$key";
        
        $name = $self->can($name) ? $self->$name () . ' ' : '';
        ...
        if ($self->can($member)) {
            $self->$member ($pos, $len);
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$key is an "atom" code from the file being parsed. If there is a handler for the atom $self->$member dispatches to the code to handle it. One neat thing about this is that a derived class can add handlers and the parser just takes it all in its stride. I reckon that's pretty cool - perhaps even elegant. :)

One way to do a binary conversion is:

my $str = '001100010011001100110001';
my $value = pack ('B*', $str);
print $value;
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