Adding ConstantScope module, which simulates Ruby's constant lookup s…

…emantics.

jake.yml

@@ -9,6 +9,7 @@ packages:
   class:            class
   package:          package
   comparable:       comparable
+  constant_scope:   constant_scope
   enumerable:       enumerable
   observable:       observable
   forwardable:      forwardable
@@ -29,6 +30,7 @@ bundles:
     - enumerable
     - observable
     - forwardable
+    - constant_scope
     - decorator
     - proxy
     - command

source/constant_scope.js

@@ -0,0 +1,45 @@
+JS.ConstantScope = new JS.Module({
+  extend: {
+    included: function(base) {
+      base.__consts__ = new JS.Module();
+      base.extend(this.ClassMethods);
+      base.include(base.__consts__);
+      base.extend(base.__consts__);
+    },
+
+    ClassMethods: new JS.Module({
+      extend: function() {
+        var constants = JS.ConstantScope.extract(arguments[0], this);
+        this.__consts__.include(constants);
+        this.callSuper();
+      },
+
+      include: function() {
+        var constants = JS.ConstantScope.extract(arguments[0], this);
+        this.__consts__.include(constants);
+        this.callSuper();
+      }
+    }),
+
+    extract: function(inclusions, base) {
+      if (!inclusions) return null;
+      if (inclusions.isA && inclusions.isA(JS.Module)) return null;
+      var constants = {}, key, object;
+      for (key in inclusions) {
+
+        if (!/^[A-Z]/.test(key)) continue;
+
+        object = inclusions[key];
+        constants[key] = object;
+        delete inclusions[key];
+
+        if (object.isA && object.isA(JS.Module)) {
+          object.include(this);
+          object.include(base.__consts__);
+          object.extend(base.__consts__);
+        }
+      }
+      return constants;
+    }
+  }
+});