Module: Immutable::ClassMethods

Defined in:
lib/immutable.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.allow_method_override ⇒ Object

module_eval



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# File 'lib/immutable.rb', line 59

def self.allow_method_override
  instance_variable_set("@#{UNIQ}_in_method_added", true)
  yield
ensure
  instance_variable_set("@#{UNIQ}_in_method_added", false)
end

.in_method_added? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/immutable.rb', line 66

def self.in_method_added?
  instance_variable_get("@#{UNIQ}_in_method_added")
end

Instance Method Details

#immutable_method(*args) ⇒ Object Also known as: immutable_methods 



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# File 'lib/immutable.rb', line 12

def immutable_method(*args)
  # Initialize variables
  @immutable_methods = [] if @immutable_methods.nil?
  @silent_immutable_methods = [] if @silent_immutable_methods.nil?
  instance_variable_set("@#{UNIQ}_in_method_added", false)

  opts = args.last.is_a?(Hash) ? args.pop : {}
  
  args.each do |method|
    alias_method "#{UNIQ}_old_#{method}", method
  end
  
  # Build list of immutable methods
  @immutable_methods += args
  @silent_immutable_methods += args if opts[:silent]

  @opts = opts
  module_eval do
    def self.method_added(sym)
      if @immutable_methods
        @immutable_methods.each do |method|
          if method && sym == method.to_sym && !in_method_added?
            unless @silent_immutable_methods.include?(method)
              raise CannotOverrideMethod, "Cannot override the immutable method: #{sym}"
            end
            
            allow_method_override do
              self.module_eval <<-"end;"
                def #{method}(*args, &block)
                  #{UNIQ}_old_#{method}(*args, &block)
                end
              end;
            end
          end 
        end # @args.each
      end # @immutable_methods
    end # def self.method_added()

    def self.method_undefined(sym)
      method_added(sym)
    end

    def self.method_removed(sym)
      method_added(sym)
    end
  end # module_eval

  def self.allow_method_override
    instance_variable_set("@#{UNIQ}_in_method_added", true)
    yield
  ensure
    instance_variable_set("@#{UNIQ}_in_method_added", false)
  end

  def self.in_method_added?
    instance_variable_get("@#{UNIQ}_in_method_added")
  end
end