Add new methods `Module#{>,>=,<=>}`; ref
@@ -35,4 +35,55 @@ class Module
end
end
+ ##
+ # call-seq:
+ # mod > other -> true, false, or nil
+ #
+ # Returns true if `mod` is an ancestor of `other`. Returns
+ # <code>nil</code> if there's no relationship between the two.
+ # (Think of the relationship in terms of the class definition:
+ # "class A < B" implies "B > A".)
+ #
+ def >(other)
+ if self.equal?(other)
+ false
+ else
+ self >= other
+ end
+ end
+
+ ##
+ # call-seq:
+ # mod >= other -> true, false, or nil
+ #
+ # Returns true if `mod` is an ancestor of `other`, or the
+ # two modules are the same. Returns
+ # <code>nil</code> if there's no relationship between the two.
+ # (Think of the relationship in terms of the class definition:
+ # "class A < B" implies "B > A".)
+ #
+ def >=(other)
+ raise TypeError, 'compared with non class/module' unless other.is_a?(Module)
+ return other < self
+ end
+
+ ##
+ # call-seq:
+ # module <=> other_module -> -1, 0, +1, or nil
+ #
+ # Comparison---Returns -1, 0, +1 or nil depending on whether `module`
+ # includes `other_module`, they are the same, or if `module` is included by
+ # `other_module`.
+ #
+ # Returns `nil` if `module` has no relationship with `other_module`, if
+ # `other_module` is not a module, or if the two values are incomparable.
+ #
+ def <=>(other)
+ return 0 if self.equal?(other)
+ return nil unless other.is_a?(Module)
+ cmp = self < other
+ return -1 if cmp
+ return 1 unless cmp.nil?
+ return nil
+ end
end
