{   my %h = ( x=>5, y=>8 );
    while ( my ($r,$s) = each %h ) {
        ...
    }
}

##</code><code>##

for ({ x=>5, y=>8 }) {
    while ( my ($r,$s) = each %$_ ) {
        ...
    }
}

##</code><code>##

for (paired( x=>5, y=>8 )) {
    my ($r,$s) = @$_;
    ...
}

##</code><code>##

sub paired {
    my @pairs;
    push @pairs, [ shift, shift ] while @_;
    return @pairs;
}

##</code><code>##

paired {
    my ($r,$s) = @_;
    ...
} ( x=>5, y=>8 );

##</code><code>##

sub paired(&@) {
    my $cb = shift;
    my @rv;
    push @rv, $cb->(shift, shift) while @_;
    return @rv;
}