Iterating your splicing map over the same array its block modifies as a side effect is a really dirty approach though; no wonder you have to test $_ to guard against its failures. The right way to do this is in two steps: 
my @spliced;
push @spliced, [ splice @_, 0, $num_elements ] while @_;
my @result = map func1($_), @spliced;

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or maybe the straightforward 
my @result;
push @result, func1([ splice @_, 0, $num_elements ]) while @_;

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It's awkward in Perl 5, that's true. Perl 6 is going to do away with this limitation of the list iteration functions and operators.

Makeshifts last the longest.

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

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