The first fills unused subarray elements with undef.

This gets rid of the undefs. 

sub groups_of_n
{
  my $n = shift;
  return
     map { [ grep {defined} @$_ ] }
     map { [ @_ [$_ * $n .. $_ * $n + $n -1 ]] }
     0 .. $#_ / $n;
}

[download]

Cheers,

JohnGG

In reply to Re^2: Syntactically cool list of lists by johngg
in thread Syntactically cool list of lists by jettero

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