Another approach, also using List::Util::max(), but using an array slice rather than splice:

c:\@Work\Perl>perl -wMstrict -le "use List::Util qw(max); ;; my @ra = qw(a b c d e f g h); ;; my $n = 3; for my $i (0 .. $#ra) { my @triplet = @ra[ max(0, $i - $n + 1) .. $i ]; printf q{'%s' }, join '', @triplet; } " 'a' 'ab' 'abc' 'bcd' 'cde' 'def' 'efg' 'fgh'
(The call to  max() could be replaced with a  ?: ternary if necessary.)


Give a man a fish:  <%-{-{-{-<


In reply to Re^5: Sub-setting an Array by AnomalousMonk
in thread Sub-setting an Array by kgherman

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