NilClass#[]

[trans]

class NilClass
  # Simply returns nil.
  #
  # Useful for something like:
  #
  #   if some_hash[:a][:b]
  #   # (where some_hash is a hash of hashes)
  #
  # which would throw a NoMethodError if some_hash didn't have a value for :a.
  #
  # I haven't had any problems using this yet, but it has the possibility of
  # causing some problems with libraries that depend on the other behavior.
  def [](key)
    nil
  end
end

Example of NilClass#[] defined to see the difference.

some_hash = {}

if some_hash[:a][:b]
  puts("got in")
else
  puts("didn't get in")
end

[trans]

While it would certainly be convenient in many cases, it probably would break a good number of programs too. For this reason I think it has to be rejected.

[ioquatix]

This is fixed by ruby's new &. operator.