use Carp 'croak';
use Storable 'nfreeze';
use Scalar::Util qw(weaken blessed reftype refaddr);
-use List::Util qw(first);
use Sub::Quote qw(qsub quote_sub);
# Already correctly prototyped: perlbrew exec perl -MStorable -e 'warn prototype \&Storable::dclone'