for @foo -> \element { say element }

##</code><code>##

my %hash;
my \foo = %hash<FOO>;
dd %h;      # Hash %h = {}
foo = 42;
dd %h;      # Hash %h = {:FOO(42)}

##</code><code>##

$ perl6 -e 'say BAR'
===SORRY!=== Error while compiling -e
Undeclared name:
    BAR used at line 1

##</code><code>##

use DBI:from<Perl5>;
use DBD::mysql:from<Perl5>;
my $dbh = DBI.connect(...);   # call DBI->connect(...) under the hood