You could keep using splice and achieve your goal by using a sub. 

sub group {
   my $n = shift;
   my @rv;
   push @rv, [ splice(@_, 0, $n) ] while @_;
   return @rv;
}

my @rv = group($C, @list);

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Update: Woops! Fixed issue brought up by haukex in reply.

In reply to Re: List into two-dimensional array by ikegami
in thread List into two-dimensional array by Anonymous Monk

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