use strict;
use warnings;
;;
sub hiya { print 'hi from ', (caller(1))[3]; }
;;
sub _x_foo { hiya; };
sub _x_bar { hiya; };
;;
my %disp = (
  foo => \&_x_foo,
  bar => \&_x_bar,
  zot => \&_x_zot,
);
dd \%disp;
;;
$disp{foo}->();
$disp{zot}->();
$disp{bar}->();