use Attribute::Handlers;

    sub myattr :ATTR {
        my($func, $symbol, $code) = @_;

        no warnings 'redefine';

        *{$symbol} = sub { 
            print "Before\n";
            $code->();
        }
    }
    
    sub somefunc :myattr {
        print "somefunc!\n";
    }

    somefunc();