--- /dev/null
+/* -*- C++ -*- ------------------------------------------------------------
+
+Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
+
+The Configurable Math Library (CML) is distributed under the terms of the
+Boost Software License, v1.0 (see cml/LICENSE for details).
+
+ *-----------------------------------------------------------------------*/
+/** @file
+ * @brief
+ */
+
+#ifndef external_h
+#define external_h
+
+namespace cml {
+
+/** This is a selector for external 1D and 2D arrays.
+ *
+ * The external<> struct is used only to select a 1D or 2D array as the
+ * base class of a vector or matrix. The rebind<> template is used by
+ * quaternion<> to select its vector length in a generic way.
+ *
+ * @sa fixed
+ * @sa dynamic
+ */
+template<int Dim1 = -1, int Dim2 = -1> struct external {
+
+ /** Rebind to a 1D type.
+ *
+ * This is used by quaternion<>.
+ */
+ template<int D> struct rebind { typedef external<D> other; };
+};
+
+} // namespace cml
+
+#endif
+
+// -------------------------------------------------------------------------
+// vim:ft=cpp