sub testit{ print 'hi' }

sub doit (&) { $_[0]->() }

$codeRef = \&testit;
doit { &$codeRef };

##</code><code>##

#!/usr/bin/perl
use Carp qw(cluck);
sub testit{ cluck 'hi',$/ };; 
sub doit (&) { print $_[0],$/;$_[0]->() };; 
$codeRef = \&testit;;
doit { &$codeRef };
__END__
CODE(0x955737c)
hi
 at coderef.pl line 3
        main::testit called at coderef.pl line 6
        main::__ANON__() called at coderef.pl line 4
        main::doit('CODE(0x955737c)') called at coderef.pl line 6

##</code><code>##

#!/usr/bin/perl
use Carp qw(cluck);
sub testit{ cluck 'hi',$/ };; 
sub doit (&) { print $_[0],$/;$_[0]->() };; 
$codeRef = \&testit;;
doit \&{ $codeRef };
__END__
CODE(0x9f4c11c)
hi
 at coderef.pl line 3
        main::testit() called at coderef.pl line 4
        main::doit('CODE(0x9f4c11c)') called at coderef.pl line 6