List::MoreUtils has pairwise and natatime, the former which works like a two-at-a-time map and the later makes an iterator that you kick in a while loop.

Example:

    my @x = ('a' .. 'g');
    my $it = natatime 3, @x;
    while (my @vals = $it->())
    {
        print "@vals\n";
    }

This prints

    a b c
    d e f
    g
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