From: Simon Strandgaard <neoneye@...>
Date: 2004-08-14T20:20:46+09:00
Subject: [RCR] Array#transpose way of dealing with nil's

At the moment #transpose rejects nil values.
It could be really nice if one tell #transpose that it
whenever it meets a nil entry.. that a nil value also should be outputted.

[[1, 2], [3, 4], nil, [5, 6]].transpose(true)   
#=> [[1, 3, nil, 5], [2, 4, nil, 6]]


I often find myself needing this for unittesting.. like this 

def generic_test_bracket_matcher(str, inpos, expected_xs, expected_ys)
  res = inpos.map {|p| str.match_bracket(p) }
  ys, xs = res.transpose    # BOOM: this doesn't like nil elements
  assert_equal(expected_xs, xs)
  assert_equal(expected_ys, ys)
end

--
Simon Strandgaard