Class: Rake::LinkedList::EmptyLinkedList

Inherits:
LinkedList
  • Object
show all
Defined in:
lib/rake/linked_list.rb

Overview

Represent an empty list, using the Null Object Pattern.

When inheriting from the LinkedList class, you should implement a type specific Empty class as well. Make sure you set the class instance variable @parent to the associated list class (this allows conj, cons and make to work polymorphically).

Direct Known Subclasses

InvocationChain::EmptyInvocationChain

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ EmptyLinkedList

Returns a new instance of EmptyLinkedList.



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# File 'lib/rake/linked_list.rb', line 98

def initialize
end

Class Method Details

.cons(head, tail) ⇒ Object 



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# File 'lib/rake/linked_list.rb', line 105

def self.cons(head, tail)
  @parent.cons(head, tail)
end

Instance Method Details

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rake/linked_list.rb', line 101

def empty?
  true
end