module Enumerable

This file provides a couple of ruby monkey patches.

Public Instance Methods

last(n=nil) click to toggle source

@example

ary.last     ->  obj or nil
ary.last(n)  ->  new_ary

@return

The last element(s) of self. If the enumerable is empty, the first form returns
nil, the second an empty Array.
The method is optimized to make use of reverse_each if present.

# File lib/swissmatch/location/ruby.rb, line 15
def last(n=nil)
  reverse_each_method = method(:reverse_each)
  has_reverse_each    = reverse_each_method && reverse_each_method.owner != Enumerable # native reverse_each needed
  if n then
    return_value = []
    if has_reverse_each then
      reverse_each { |val|
        return_value.unshift(val)
        return return_value if return_value.size == n
      }
    else
      each { |val|
        return_value.push(val)
        return_value.shift if return_value.size > n
      }
    end
  else
    if has_reverse_each then
      reverse_each { |value| return value }
    else
      return_value = nil
      each { |value| return_value = value }
    end
  end

  return_value
end