Iterator::ProxyLast (Class)

In: iterator.rb
Parent: Iterator::Base

Remembering The Last Value

 require 'iterator'
 ary1 = %w(a b c)
 i1 = ary1.create_iterator
 iterator = Iterator::ProxyLast.new(i1)
 result = []
 while iterator.has_next?
   result << [iterator.last_value, iterator.current]
   iterator.next
 end
 iterator.close
 i1.close
 p result  # [[nil, "a"], ["a", "b"], ["b", "c"]]

This class is bidirectional, so reverse is therefore possible.

Methods

new  

Attributes

i  [R]  iterator that is wrapped by us
last_value  [R]  caching of the last element

Public Class methods

new(iterator, last_value=nil)

Create an instance of ProxyLast. Must supplied an iterator. The last_value is optional, and is only being used in the first iteration. 

 i1 = "hello".split(//).create_iterator
 iterator = Iterator::ProxyLast.new(i1, 'border')

[Validate]