From 6674648590bdf9996d1c8203b68f8d3059680cd8 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Wed, 7 Sep 2016 14:39:05 -0700
Subject: [PATCH] ircd::util: Add util for template based nothrow overloading.

---
 include/ircd/util.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/include/ircd/util.h b/include/ircd/util.h
index 66017befb..b62eeeec0 100644
--- a/include/ircd/util.h
+++ b/include/ircd/util.h
@@ -337,6 +337,27 @@ struct _TEST_SIZEOF_;
 #define IRCD_TEST_SIZEOF(name) \
 	ircd::util::_TEST_SIZEOF_<sizeof(name)> _test_;
 
+
+/* This is a template alternative to nothrow overloads, which
+ * allows keeping the function arguments sanitized of the thrownness.
+ */
+
+template<class exception_t>
+constexpr bool
+is_nothrow()
+{
+	return std::is_same<exception_t, std::nothrow_t>::value;
+}
+
+template<class exception_t  = std::nothrow_t,
+         class return_t     = bool>
+using nothrow_overload = typename std::enable_if<is_nothrow<exception_t>(), return_t>::type;
+
+template<class exception_t,
+         class return_t     = void>
+using throw_overload = typename std::enable_if<!is_nothrow<exception_t>(), return_t>::type;
+
+
 }        // namespace util
 }        // namespace ircd
 #endif   // __cplusplus