From: "Shot (Piotr Szotkowski)" <shot@...>
Date: 2007-12-16T08:03:20+09:00
Subject: An idiomatic way to traverse all pairs in an enumerable?

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I seem to end up doing the following quite a lot:

enum.each do |a|
  enum.each do |b|
    next if a >=3D b
    # do_something with a and b
  end
end

In general, I=E2=80=99m looking for an idiomatic way of traversing each
possible pair of a given enum=E2=80=99s contents (once). Is there a more
compact construct?

(I assume I could finally grasp the whole block-passing side of Ruby
and write my own Enumerable#each_mix, but maybe there=E2=80=99s something t=
here
already. Note: Enumerable#each_pair doesn=E2=80=99t cut it, as it=E2=80=99s=
 just for
neighbouring element pairs, while I need something for all possible
pairs.)

Thanks in advance for any help with the above!

-- Shot
--=20
The existential root of libertarianism is the experience of
being very bad at taking orders from morons.   -- Leopold Leider

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