extreme refactoring

[chaz/yoink] / src / Moof / cml / core / meta / if.h

diff --git a/src/Moof/cml/core/meta/if.h b/src/Moof/cml/core/meta/if.h
new file mode 100644 (file)
index 0000000..1ea3235
--- /dev/null
+++ b/src/Moof/cml/core/meta/if.h
@@ -0,0 +1,42 @@
+/* -*- 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 meta_if_h
+#define meta_if_h
+
+#include <cml/core/meta/common.h>
+
+namespace cml {
+
+/** Select argument type based upon truth value. */
+template<bool yn, typename TrueT, typename FalseT> struct select_if;
+
+/** Result is TrueT if true. */
+template<typename TrueT, typename FalseT>
+struct select_if<true,TrueT,FalseT> {
+    typedef TrueT result;
+    enum { is_true = true };
+};
+
+/** Result is FalseT if false. */
+template<typename TrueT, typename FalseT>
+struct select_if<false,TrueT,FalseT> {
+    typedef FalseT result;
+    enum { is_true = false };
+};
+
+} // namespace cml
+
+#endif
+
+// -------------------------------------------------------------------------
+// vim:ft=cpp