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The index variables there kept tickling me as not right. This is Perl, not C, there has to be a way to do this without explicit indices and no copying. Guess what. :) It's actually simpler than I was expecting and definitely goes in my "cool snippets" file.
sub mapn (&@) { my ($cb, $n) = splice @_, 0, 2; splice @_, 0, 0, (undef)x$n; map{ splice @_, 0, $n; $cb->(@_[0 .. (@_ < $n ? $#_ : $n-1)]); } 0 .. (@_/$n)-1; } sub mapnz (&@) { my ($cb, $n) = splice @_, 0, 2; splice @_, 0, 0, (undef)x$n; map{ splice @_, 0, $n; $cb->(@_[0 .. $n-1]); } 0 .. (@_/$n)-1; }

BrowserUk++ for the inspiration!

Update: fixed mapnz

Makeshifts last the longest.


In reply to Re^2: Fold a list using map splices by Aristotle
in thread Fold a list using map splices by hiseldl

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