Another way: 

sub testit{ print 'hi' }

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

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

[download]

update (after BrowserUk's response below) -

My suggestion adds next to nothing, since wrt to sub stacks, $ref->() is just syntactic sugar for &$ref or vice versa. The notation doit \&{ $subref } seems to be the right thing to do: 

#!/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

[download]
#!/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

[download]

In reply to Re^3: The & prototype and code references in scalars. by shmem
in thread The & prototype and code references in scalars. by BrowserUk

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