ruby - Dynamic metaprogrammed methods on inheritance -

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• in ruby, there way 'override' constant in subclass inherited methods use new constant instead of old? 1 answer

excuse me example; trying develop independent example present requirement, may appear contrived:

class animal   name = 'no name'    %w(bark walk).each |action|     define_method(action)       name + ' ' + action     end   end end  class pig < animal   name = 'piggie' end  animal.new.walk # => "no name walk" pig.new.walk # => "no name walk" 

the last line expected return "piggie walk", doesn't. why happen , how make use constant defined in pig?

try this

class animal   def initialize     @name ||= "no name"   end     %w(bark walk).each |action|     define_method(action)       "#{@name} #{action}"     end    end  end  class pig < animal   def initialize     @name = 'piggie'   end  end  animal.new.walk # => "no name walk" pig.new.walk