method

extlib_inheritable_reader

v3.0.9 - 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 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 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

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