CODE EXAMPLE FOR RUBY

ruby delete method

# How to delete class/singleton methods

# define an empty class
class Foo; end

# show all class/singleton methods of Foo
p Foo.singleton_methods #=> []

# add the `bar` method
class Foo
  def self.bar
    puts "I'm Foo::bar!"
  end
end

p Foo.singleton_methods #=> [:bar]
Foo.bar #=> I'm Foo::bar!

# delete the method
Foo.singleton_class.undef_method(:bar)
p Foo.singleton_methods #=> []
Foo.bar #=> undefined method `bar' for Foo:Class (NoMethodError)