0001-Add-and-casecmp-to-Symbol.patch

From 6255dd5f7263624e36295d21b0180fc88c599621 Mon Sep 17 00:00:00 2001
From: Joshua Miller <[email protected]>
Date: Thu, 19 May 2011 19:13:28 -0700
Subject: [PATCH] Add #<=> and #casecmp to Symbol

---
 kernel/common/symbol.rb |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/kernel/common/symbol.rb b/kernel/common/symbol.rb
index 42369bd..a01d3f7 100644
--- a/kernel/common/symbol.rb
+++ b/kernel/common/symbol.rb
@@ -38,6 +38,25 @@ class Symbol
   alias_method :intern, :to_sym
   alias_method :id2name, :to_s
 
+
+  ##
+  # Comparison --- Returns -1 if <i>other</i> is less than, 0 if 
+  # <i>other</i> is equal, and +1 if <i>other</i> is greater than
+  # <i>self</i>.  Comparison is provided by <code>String#<=></code>.
+  def <=>(other)
+    return unless other.respond_to?(:to_sym) && other.respond_to?(:<=>)
+    self.to_s <=> other.to_sym.to_s
+  end
+
+  ##
+  # Case-insensitive version of <code>Symbol#<=></code>. Similarly 
+  # relies on <code>String#casecmp</code> using string representations 
+  # of <i>self</i> and <i>other</i>
+  def casecmp(other)
+    return unless other.respond_to?(:to_sym) && other.respond_to?(:<=>)
+    self.to_s.casecmp(other.to_sym.to_s)
+  end
+
   # Returns a Proc object which respond to the given method by sym.
   def to_proc
     # Put sym in the outer enclosure so that this proc can be instance_eval'd.
-- 
1.7.0.4

Why is there a check for '&& other.respond_to?(:<=>)' in #<=> ? self.to_s is sent #<=>

Also, why is there '&& other.respond_to?(:<=>)' in #casecmp ?