I just found this piece of code. This is how each_array is defined in List::MoreUtils. What it does is generate an iterator for iterating over multiple lists at the same time which is pretty useful. 

sub each_array (\@;\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@)
{
    return each_arrayref(@_);
}

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But what is striking is that you can call it like this and not worry that the lists will get merged before they will be used inside each_array 
    my $ea = each_array(@a, @b, @c);
    while ( my ($a, $b, $c) = $ea->() )   { .... }

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I know that \@;\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@ is supposed to be some sort of prototype , I don't really understand what it does, what does this do ?

In reply to interesting prototype by spx2

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