ruby-enterprise-edition: use new dsl

Formula/ruby-enterprise-edition.rb

@@ -1,28 +1,26 @@
 require 'formula'
 
 class RubyEnterpriseEdition < Formula
+  homepage 'http://rubyenterpriseedition.com/'
   url 'http://rubyenterpriseedition.googlecode.com/files/ruby-enterprise-1.8.7-2011.03.tar.gz'
   md5 '038604ce25349e54363c5df9cd535ec8'
-  homepage 'http://rubyenterpriseedition.com/'
+
+  skip_clean 'bin/ruby'
+
+  option 'enable-shared', "Compile shared, but see caveats"
 
   depends_on 'readline'
 
   fails_with :llvm
 
-  skip_clean 'bin/ruby'
-
-  def options
-    [['--enable-shared', "Compile shared, but see caveats."]]
-  end
-
   def install
     readline = Formula.factory('readline').prefix
 
-    args = ['./installer', "--auto", prefix, '--no-tcmalloc']
-    args << '-c' << '--enable-shared' if ARGV.include? '--enable-shared'
+    args = ["--auto", prefix, '--no-tcmalloc']
+    args << '-c' << '--enable-shared' if build.include? 'enable-shared'
     # Configure will complain that this is an unknown option, but it is actually OK
     args << '-c' << "--with-readline-dir=#{readline}"
-    system *args
+    system './installer', *args
   end
 
   def caveats; <<-EOS.undent