Add methods for debugging only when RUBY_DEBUG

Author: Satoshi Tagomori

namespace.c

@@ -826,6 +826,18 @@ Init_enable_namespace(void)
 
 #ifdef RUBY_DEBUG
 
+static VALUE
+rb_namespace_s_root(VALUE recv)
+{
+    return root_namespace->ns_object;
+}
+
+static VALUE
+rb_namespace_s_main(VALUE recv)
+{
+    return main_namespace->ns_object;
+}
+
 static const char *
 classname(VALUE klass)
 {
@@ -990,6 +1002,8 @@ Init_Namespace(void)
         rb_include_module(rb_cObject, rb_mNamespaceLoader);
 
 #ifdef RUBY_DEBUG
+        rb_define_singleton_method(rb_cNamespace, "root", rb_namespace_s_root, 0);
+        rb_define_singleton_method(rb_cNamespace, "main", rb_namespace_s_main, 0);
         rb_define_global_function("dump_classext", rb_f_dump_classext, 1);
 #endif
     }