Fixed Range#last for 1.9.

kernel/common/range.rb

@@ -70,7 +70,6 @@ def inspect
   end
 
   attr_reader :end
-  alias_method :last, :end
 
   def step(step_size=1) # :yields: object
     return to_enum(:step, step_size) unless block_given?

kernel/common/range18.rb

@@ -40,6 +40,7 @@ def each(&block)
   end
 
   alias_method :first, :begin
+  alias_method :last, :end
 
   protected
 

kernel/common/range19.rb

@@ -51,6 +51,10 @@ def first(n=undefined)
     n.equal?(undefined) ? @begin : super
   end
 
+  def last(n=undefined)
+    n.equal?(undefined) ? @end : to_a.last(n)
+  end
+
   def max(&block)
     return super(&block) if block_given? || (@excl && !@end.kind_of?(Numeric))
     return nil if @end < @begin || (@excl && @end == @begin)