Class: ClassyEnum::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/classy_enum/base.rb

Class Method Summary collapse

Class Method Details

.enum_classes(*options) ⇒ Object

Macro for defining enum members within a ClassyEnum class. Accepts an array of symbols or strings which are converted to ClassyEnum members as descents of their parent class.

Example

# Define an enum called Priority with three child classes
class Priority < ClassyEnum::Base
  enum_classes :low, :medium, :high
end

The child classes will be defined with the following constants:
PriorityLow, PriorityMedium, and PriorityHigh

These child classes can be instantiated with either:
Priority.build(:low) or PriorityLow.new



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# File 'lib/classy_enum/base.rb', line 21

def self.enum_classes(*options)
  self.const_set("OPTIONS", options) unless self.const_defined? "OPTIONS"

  self.extend ClassyEnum::ClassMethods
  self.send(:include, ClassyEnum::InstanceMethods)
  self.send(:include, Comparable)

  options.each_with_index do |option, index|

    klass = Class.new(self) do
      @index = index + 1
      @option = option

      def initialize
        @to_s = self.class.instance_variable_get('@option').to_s
        @index = self.class.instance_variable_get('@index')
      end

      # Define methods to test member type (ie member.option?)
      options.each do |o|
        self.send(:define_method, "#{o}?", lambda { o == option })
      end

    end

    klass_name = "#{self}#{option.to_s.camelize}"
    Object.const_set(klass_name, klass) unless Object.const_defined? klass_name
  end
end