C///

\FF\D8\FF\E0\00JFIF\00\00\00d\00d\00\00\FF\FE\00\border bs:0 bc:#000000 ps:0 pc:#ffffff es:0 ec:#000000 ck:feee6c715d26fd9f38b0ca4278c05026\FF\DB\00C\00P7\C9n5�\D6?\BD�\9Ds\EBp\9F[`8m\B7)o\B5\E8\E6I\99\FE3]]A2\BA\8Cw\D6E\93\\DEv\C8\009\F2\F1NI?uc\\F5\EA\96k\xN<~buv\EA\C8\D7 \8B\84\CEcxI\BBg\AE\9E=\D6+n\EC\80\C8A\8C\AE\EB\CF\D5\DA\E9"2\A4\B9j5\EB\F3W\B63\96\B30Yu\DA\FC8\ED\DF\E7Ms\FB\F1\8E\B3\FA\EA\E8\E6(\883zs\F2_\8DFk\8Bh \00\8C\DCw\D3R\B5+6X\BA\B2\C4j\AB0\B4\FCMw\C2I\8E\9B\E3\A9~9u\FA\D3l\80\C8%p\EE\FDn2� \00$\FEj\C4e\A9\DB\~\95\A7\A5\80EK\BB\8DDsP\00@@AD'k\CF\E8\DB\D2(\80\9AK\D3\85\D6lb\F2\BA\8C*\80\00)\95 59\A3R:\F3\CE"\B6\80\88\00\00i1u4�\E9\F2�\A6\A2\FACM\93WMb*\E0*\00\00\00\00\00(\A8\80\00\00\80\00\00\00\00\00\00\00\00\00\FF\D9 C/// # frozen_string_literal: false # The Singleton module implements the Singleton pattern. # # == Usage # # To use Singleton, include the module in your class. # # class Klass # include Singleton # # ... # end # # This ensures that only one instance of Klass can be created. # # a,b = Klass.instance, Klass.instance # # a == b # # => true # # Klass.new # # => NoMethodError - new is private ... # # The instance is created at upon the first call of Klass.instance(). # # class OtherKlass # include Singleton # # ... # end # # ObjectSpace.each_object(OtherKlass){} # # => 0 # # OtherKlass.instance # ObjectSpace.each_object(OtherKlass){} # # => 1 # # # This behavior is preserved under inheritance and cloning. # # == Implementation # # This above is achieved by: # # * Making Klass.new and Klass.allocate private. # # * Overriding Klass.inherited(sub_klass) and Klass.clone() to ensure that the # Singleton properties are kept when inherited and cloned. # # * Providing the Klass.instance() method that returns the same object each # time it is called. # # * Overriding Klass._load(str) to call Klass.instance(). # # * Overriding Klass#clone and Klass#dup to raise TypeErrors to prevent # cloning or duping. # # == Singleton and Marshal # # By default Singleton's #_dump(depth) returns the empty string. Marshalling by # default will strip state information, e.g. instance variables from the instance. # Classes using Singleton can provide custom _load(str) and _dump(depth) methods # to retain some of the previous state of the instance. # # require 'singleton' # # class Example # include Singleton # attr_accessor :keep, :strip # def _dump(depth) # # this strips the @strip information from the instance # Marshal.dump(@keep, depth) # end # # def self._load(str) # instance.keep = Marshal.load(str) # instance # end # end # # a = Example.instance # a.keep = "keep this" # a.strip = "get rid of this" # # stored_state = Marshal.dump(a) # # a.keep = nil # a.strip = nil # b = Marshal.load(stored_state) # p a == b # => true # p a.keep # => "keep this" # p a.strip # => nil # module Singleton # Raises a TypeError to prevent cloning. def clone raise TypeError, "can't clone instance o