Singleton class extended by a module with module_function

Ruby Development
1

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% cat z.rb
module M
module_function
def m
p :m
end
end

class C
end

class << C
include M
end

C.m
% ruby -v z.rb
ruby 1.9.0 (2008-03-11 revision 15748) [i686-linux]
:m
% ruby-1.8 -v z.rb
ruby 1.8.6 (2008-03-11 patchlevel 5000) [i686-linux]
z.rb:15: private method `m’ called for C:Class (NoMethodError)

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