From 9286cfa8cce6dcfd7ede7a0b7a2c856e98b4f62a Mon Sep 17 00:00:00 2001
From: Denis Blank <denis.blank@outlook.com>
Date: Wed, 24 Jan 2018 23:05:23 +0100
Subject: [PATCH] Feature detection placeholders

---
 include/continuable/detail/features.hpp | 15 +++++++++++----
 test/unit-test/test-continuable.hpp     |  3 +--
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/include/continuable/detail/features.hpp b/include/continuable/detail/features.hpp
index 16035fa..b083dae 100644
--- a/include/continuable/detail/features.hpp
+++ b/include/continuable/detail/features.hpp
@@ -55,10 +55,17 @@
 #undef CONTINUABLE_WITH_EXCEPTIONS
 #endif
 
-/// TODO Enable this
-#undef CONTINUABLE_HAS_CXX17_CONSTEXPR_IF
-/// TODO Enable this
-#undef CONTINUABLE_HAS_CXX17_FOLD_EXPRESSION
+#if defined(__has_feature)
+#if __has_feature(cxx_if_constexpr)
+// PR not merged into the clang master yet
+#define CONTINUABLE_HAS_CXX17_CONSTEXPR_IF
+#endif
+
+#if __has_feature(cxx_fold_expressions)
+// PR not merged into the clang master yet
+#define CONTINUABLE_HAS_CXX17_FOLD_EXPRESSION
+#endif
+#endif
 
 /// This is enabled by the CMake project
 // #undef CONTINUABLE_HAS_EXPERIMENTAL_COROUTINE
diff --git a/test/unit-test/test-continuable.hpp b/test/unit-test/test-continuable.hpp
index 803b33f..b06dcda 100644
--- a/test/unit-test/test-continuable.hpp
+++ b/test/unit-test/test-continuable.hpp
@@ -207,8 +207,7 @@ auto make_step(T* me, unsigned& current, unsigned step) {
 
 #if !defined(CONTINUABLE_WITH_NO_EXCEPTIONS)
 struct test_exception : std::exception {
-  explicit test_exception() {
-  }
+  explicit test_exception() = default;
 
   bool operator==(test_exception const&) const noexcept {
     return true;