difference between attr_accessor and initialize

attr_accessor is used to create setter and getter methods for instance variables so that they can be accessed outside the class. initialize is the special method in ruby that gets called when an object is instantiated.

class Birthday
 attr_accessor :name
 
 def initialize age, gender
   @age = age
   self.gender = gender
 end
end

bday = Birthday.new "30", "Male"
puts bday.name # nil as initializer dont have name. yields results if set in before step like bday.name = "Bob"
puts bday.age    # undefined method `age`  as no attr_reader defined for age
puts bday.gender # undefined method `gender=' as no attr_writer defined for gender

# to fix the issues

class Birthday
 attr_accessor :name, :gender, :age
 
 def initialize age, gender, name
   @age = age
   self.gender = gender ## call attr_writer of @gender
   @name = name
 end
end

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Posted by Sandheep to Sandheep's deck (2013-05-22 18:33)

difference between attr_accessor and initialize

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