From b77295d7dee6747f560a61f43daf902b62b85462 Mon Sep 17 00:00:00 2001
From: knu <knu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 7 May 2009 17:35:55 +0000
Subject: [PATCH] * lib/set.rb (SortedSet#add): Do not require each newly added
   element to be Comparable but to respond to <=>. [ruby-dev:38371]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@23365 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog  | 5 +++++
 lib/set.rb | 8 ++++----
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 6ad8d9706d..9841698673 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri May  8 02:34:25 2009  Akinori MUSHA  <knu@iDaemons.org>
+
+	* lib/set.rb (SortedSet#add): Do not require each newly added
+	  element to be Comparable but to respond to <=>. [ruby-dev:38371]
+
 Thu May  7 13:58:52 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* range.c (range_eql): fixed rdoc.
diff --git a/lib/set.rb b/lib/set.rb
index b352cdd991..3723c8e050 100644
--- a/lib/set.rb
+++ b/lib/set.rb
@@ -446,8 +446,8 @@ end
 # yielded in sorted order (according to the return values of their
 # #<=> methods) when iterating over them.
 # 
-# All elements that are added to a SortedSet must include the
-# Comparable module.
+# All elements that are added to a SortedSet must respond to the <=>
+# method for comparison.
 # 
 # Also, all elements must be <em>mutually comparable</em>: <tt>el1 <=>
 # el2</tt> must not return <tt>nil</tt> for any elements <tt>el1</tt>
@@ -496,7 +496,7 @@ class SortedSet < Set
 	  end
 	  
 	  def add(o)
-	    o.is_a?(Comparable) or raise ArgumentError, "value must be comparable"
+	    o.respond_to?(:<=>) or raise ArgumentError, "value must repond to <=>"
 	    super
 	  end
 	  alias << add
@@ -519,7 +519,7 @@ class SortedSet < Set
 	  end
 
 	  def add(o)
-	    o.is_a?(Comparable) or raise ArgumentError, "value must be comparable"
+	    o.respond_to?(:<=>) or raise ArgumentError, "value must respond to <=>"
 	    @keys = nil
 	    super
 	  end