method

extlib_inheritable_reader

v3.0.0 - Show latest stable - 0 notes - Class: Class

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What's this?

extlib_inheritable_reader(*ivars, &block) public

Defines class-level inheritable attribute reader. Attributes are available to subclasses, each subclass has a copy of parent’s attribute.

@param *syms<Array[#to_s]> Array of attributes to define inheritable reader for. @return <Array[#to_s]> Array of attributes converted into inheritable_readers.

@api public

@todo Do we want to block instance_reader via :instance_reader => false @todo It would be preferable that we do something with a Hash passed in

  (error out or do the same as other methods above) instead of silently
  moving on). In particular, this makes the return value of this function
  less useful.

Show source

# File activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb, line 191
  def extlib_inheritable_reader(*ivars, &block)
    options = ivars.extract_options!

    ivars.each do |ivar|
      self.class_eval "def self.\#{ivar}\nreturn @\#{ivar} if self.object_id == \#{self.object_id} || defined?(@\#{ivar})\nivar = superclass.\#{ivar}\nreturn nil if ivar.nil? && !\#{self}.instance_variable_defined?(\"@\#{ivar}\")\n@\#{ivar} = ivar.duplicable? ? ivar.dup : ivar\nend\n", __FILE__, __LINE__ + 1
      unless options[:instance_reader] == false
        self.class_eval "def \#{ivar}\nself.class.\#{ivar}\nend\n", __FILE__, __LINE__ + 1
      end
      instance_variable_set("@#{ivar}""@#{ivar}", yield) if block_given?
    end
  end

extlib_inheritable_reader

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