1 files changed, 26 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/module/setup.rb b/activesupport/lib/active_support/core_ext/module/setup.rb
new file mode 100644
index 0000000000..e6dfd0cf56
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/module/setup.rb
@@ -0,0 +1,26 @@
+class Module
+  attr_accessor :_setup_block
+  attr_accessor :_dependencies
+  
+  def setup(&blk)
+    @_setup_block = blk
+  end
+  
+  def use(mod)
+    return if self < mod
+    
+    (mod._dependencies || []).each do |dep|
+      use dep
+    end
+    # raise "Circular dependencies" if self < mod
+    include mod
+    extend mod.const_get("ClassMethods") if mod.const_defined?("ClassMethods")
+    class_eval(&mod._setup_block) if mod._setup_block
+  end
+  
+  def depends_on(mod)
+    return if self < mod
+    @_dependencies ||= []
+    @_dependencies << mod
+  end
+end
+\ No newline at end of file