Implement Comparable.

[git-p4: depot-paths = "//src/metaruby/dev/": change = 2192]

Comparable.rb

@@ -0,0 +1,78 @@
+module Comparable
+
+  ##
+  # call-seq:
+  #   obj < other    => true or false
+  #
+  # Compares two objects based on the receiver's <tt><=></tt> method,
+  # returning true if it returns -1.
+
+  def <(other)
+    return (self <=> other) == -1
+  end
+
+  ##
+  # call-seq:
+  #   obj <= other    => true or false
+  #
+  # Compares two objects based on the receiver's <tt><=></tt> method,
+  # returning true if it returns -1 or 0.
+
+  def <=(other)
+    return ((self <=> other) == -1 or (self <=> other) == 0)
+  end
+
+  ##
+  # call-seq:
+  #   obj == other    => true or false
+  #
+  # Compares two objects based on the receiver's <tt><=></tt> method,
+  # returning true if it returns 0. Also returns true if <em>obj</em> and
+  # <em>other</em> are the same object.
+
+  def ==(other)
+    return (self <=> other) == 0
+  end
+
+  ##
+  # call-seq:
+  #   obj > other    => true or false
+  #
+  # Compares two objects based on the receiver's <tt><=></tt> method,
+  # returning true if it returns 1.
+
+  def >(other)
+    return (self <=> other) == 1
+  end
+
+  ##
+  # call-seq:
+  #   obj >= other    => true or false
+  #
+  # Compares two objects based on the receiver's <tt><=></tt> method,
+  # returning true if it returns 0 or 1.
+
+  def >=(other)
+    return ((self <=> other) == 1 or (self <=> other) == 0)
+  end
+
+  ##
+  # call-seq:
+  #   obj.between?(min, max)    => true or false
+  #
+  # Returns <tt>false</tt> if <em>obj</em> <tt><=></tt> <em>min</em> is less
+  # than zero or if <em>anObject</em> <tt><=></tt> <em>max</em> is greater
+  # than zero, <tt>true</tt> otherwise.
+  #
+  #    3.between?(1, 5)               #=> true
+  #    6.between?(1, 5)               #=> false
+  #    'cat'.between?('ant', 'dog')   #=> true
+  #    'gnu'.between?('ant', 'dog')   #=> false
+
+  def between?(min, max)
+    return ((self <=> min) >= 0 and (self <=> max) <= 0)
+    raise NotImplementedError, 'between? is not implemented'
+  end
+
+end
+

Makefile

@@ -18,6 +18,7 @@ CLASSES = \
 	Range \
 	Hash \
 	String \
+	Comparable \
 	$(NULL)
 
 TESTFILES = $(patsubst %,%.pass,$(CLASSES))