This doesn't use split, but is the first thing I think of: 
my $string = join '', 'a'..'z';
my @fields = $string =~ /.{1,3}/g;
my @fields2 = grep {$a=!$a} @fields;

[download]
Hmm, $string =~ /.{1,3}/g should even be faster than split /(?(?{pos() % 3})(?!))/, $string.  I guess not as fast as unpack, though.

In reply to Re: Using split() to divide a string by length by chibiryuu
in thread Using split() to divide a string by length by japhy

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