def deprecate name, repl, year, month
      class_eval {
        old = "_deprecated_#{name}"
        alias_method old, name
        define_method name do |*args, &block| # TODO: really works on 1.8.7?
          klass = self.kind_of? Module
          target = klass ? "#{self}." : "#{self.class}#"
          msg = [ "NOTE: #{target}#{name} is deprecated",
            repl == :none ? " with no replacement" : ", use #{repl}",
            ". It will be removed on or after %4d-%02d-01." % [year, month],
            "\n#{target}#{name} called from #{Gem.location_of_caller.join(":")}",
          ]
          warn "#{msg.join}." unless Gem::Deprecate.skip
          send old, *args, &block
        end
      }
    end
#
Simple deprecation method that deprecates +name+ by wrapping it up
in a dummy method. It warns on each call to the dummy method
telling the user of +repl+ (unless +repl+ is :none) and the
year/month that it is planned to go away.