Public-required members are now stored in a hash

lib/class_builder.js

@@ -60,7 +60,14 @@ var util           = require( __dirname + '/util' ),
      *
      * @type {Object.<string,boolean>}
      */
-    reserved = { '__initProps': true }
+    reserved = { '__initProps': true },
+
+    /**
+     * Hash of members that must be public
+     *
+     * @type {Object.<string,boolean}
+     */
+    public_members = { '__construct': true }
 ;
 
 
@@ -389,11 +396,13 @@ function buildMembers(
         method: function( name, func, is_abstract, keywords )
         {
             // constructor check
-            if ( name === '__construct' )
+            if ( public_members[ name ] === true )
             {
                 if ( keywords[ 'protected' ] || keywords[ 'private' ] )
                 {
-                    throw TypeError( "Constructor must be public" );
+                    throw TypeError(
+                        name + " must be public"
+                    );
                 }
             }