attributes - Ruby: How to create attr_accessor on the fly -


i want know how create attr_accessor on fly. possible like:

attr_accessor "@#{key}"

inside initialize method?

module mymodule   def initialize(parameters = {})     parameters.each |key, value|       instance_variable_set("@#{key}", value) unless value.nil?     end   end end  class myclass   include mymodule end  clazz = myclass.new attr1: "arg1", attr2: "arg2", attr3: "arg3"   # => #<myclass:0x43f6050 @attr1="arg1", @attr2="arg2", @attr3="arg3">  clazz.attr1   # !> nomethoderror: undefined method `attr1' #<myclass:0x43f6050 @attr1="arg1", @attr2="arg2", @attr3="arg3">  clazz.attr1="attr1"   # !> nomethoderror: undefined method `attr1=' #<myclass:0x43f6050 @attr1="arg1", @attr2="arg2", @attr3="arg3">

you can define per instance accessors calling attr_accessor on instance's singleton class.

class structy   def initialize(parameters = {})     parameters.each |key, value|       singleton_class.send :attr_accessor, key       instance_variable_set "@#{key}", value     end   end end

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