module StringExt
FOO = "foo 1"
def say_foo
"I'm saying " + FOO
end
end
class String
include StringExt
def say
say_foo
end
end
module OpenClassWithInclude
def self.say
String.new.say
end
def self.say_foo
String.new.say_foo
end
def self.say_with_obj(str)
str.say
end
def self.refer_foo
String::FOO
end
end