method

extlib_inheritable_reader

rails latest stable - Class: Class

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 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.

# File activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb, line 187
  def extlib_inheritable_reader(*ivars, &block)
    options = ivars.extract_options!

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

extlib_inheritable_reader

Method deprecated or moved

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