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wjlroe/call_me_maybe.rb

Created August 12, 2013 14:56
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call_me_maybe.rb
class NullObject
def method_missing(*args, &block)
self
end
def nil?; true; end
end
def Maybe(value)
value.nil? ? NullObject.new : value
end
foo = nil
buz = nil
Maybe(foo).bar.baz + buz
# => #<NullObject:0x007fad649f68c0>
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wjlroe commented Aug 12, 2013

Breaks however, if Maybe(foo).bar returns a real object and that object doesn't respond to #baz then you get NoMethodException rather than your intended nil

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