Module: TypedEnum

Included in:
Foo
Defined in:
lib/typed_enum.rb

Overview

A TypedEnum can be used to represent a typed, enumerated set of values. A TypedEnum offers the following features:

* Instances are restricted (in the absence of class-opening) to the set of instances defined in
  the class definition
* Available values can be enumerated in a consistent order via a call to the 
* #values class method
* Instances can be retrieved via class constants
* Instances can be retrieved by parsing a string/symbol
* Instances can be serialized to a string

Basic usage example:

class Color
  @enum = lambda {[
    RED   = self.new(:red),
    GREEN = self.new(:green),
    BLUE  = self.new(:blue)
  ]}
  include TypedEnum
end

Color::RED => #<Color:0x163d59f8 @name=:red>
Color.from_name(:red) => #<Color:0x163d59f8 @name=:red>
Color.from_name('red') => #<Color:0x163d59f8 @name=:red>
Color::RED.name => :red
Color.values => [#<Color:0x163d59f8 @name=:red>, #<Color:0x163d59a8 @name=:green>, #<Color:0x163d5980 @name=:blue>]

Defined Under Namespace

Modules: TypedEnumClassMethods

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/typed_enum.rb', line 30

def name
  @name
end

Class Method Details

.included(klass) ⇒ Object 



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# File 'lib/typed_enum.rb', line 83

def TypedEnum.included(klass)
  super
  klass.extend TypedEnumClassMethods
  klass.init
  klass.private_class_method :new, :allocate
end

Instance Method Details

#clone ⇒ Object

Raises:

  • (TypeError) 


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# File 'lib/typed_enum.rb', line 35

def clone
  raise TypeError, "Can't clone instance of TypedEnum #{self.class}"
end

#dump(depth = -1)) ⇒ Object 



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# File 'lib/typed_enum.rb', line 41

def dump(depth=-1)
  @name.to_s
end

#dup ⇒ Object

Raises:

  • (TypeError) 


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# File 'lib/typed_enum.rb', line 38

def dup
  raise TypeError, "Can't dup instance of TypedEnum #{self.class}"
end

#initialize(name) ⇒ Object 



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# File 'lib/typed_enum.rb', line 31

def initialize(name)
  @name = name
end