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rubysingletoninitializationrubymotion

initializing ruby singleton


I'm trying to initializing a singleton in ruby. Here's some code:

class MyClass
  attr_accessor :var_i_want_to_init

  # singleton
  @@instance = MyClass.new
  def self.instance
    @@instance
  end

  def initialize # tried 1. initialize, 2. new, 3. self.initialize, 4. self.new
    puts "I'm being initialized!"
    @var_i_want_to_init = 2
  end
end

The problem is that initialize is never called and thus the singleton never initialized. I tried naming the init method initialize, self.initialize, new, and self.new. Nothing worked. "I'm being initialized" was never printed and the variable never initialized when I instantiated with

my_var = MyClass.instance

How can I setup the singleton so that it gets initialized? Help appreciated,

Pachun


Solution

  • Rubymotion (1.24+) now seems to support using GCD for singleton creation

    class MyClass
      def self.instance
        Dispatch.once { @instance ||= new }
        @instance
      end
    end