From 9a07fc2496b649b027c4c7bdaf47a4b138013940 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Wed, 6 Sep 2017 13:41:01 +1000
Subject: [PATCH] except: add try_array

---
 except.hpp | 33 +++++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/except.hpp b/except.hpp
index a4c0367..d6b305e 100644
--- a/except.hpp
+++ b/except.hpp
@@ -12,7 +12,7 @@
  * limitations under the License.
  *
  * Copyright:
- *      2016, Danny Robson <danny@nerdcruft.net>
+ *      2016-2017, Danny Robson <danny@nerdcruft.net>
  */
 
 #ifndef CRUFT_VK_EXCEPT_HPP
@@ -20,6 +20,9 @@
 
 #include "./vk.hpp"
 
+#include <cruft/util/debug.hpp>
+#include <cruft/util/types/traits.hpp>
+
 #include <exception>
 #include <functional>
 #include <type_traits>
@@ -42,7 +45,7 @@ namespace cruft::vk {
         try_func (FuncT &&func, Args &&...args)
         {
             static_assert(std::is_same_v<
-                std::result_of_t<FuncT(Args...)>,
+                typename func_traits<FuncT>::return_type,
                 VkResult
             >);
 
@@ -61,6 +64,32 @@ namespace cruft::vk {
             try_func (func, std::forward<Args> (args)..., &value);
             return value;
         }
+
+
+        template <
+            template <typename...> class ContainerT,
+            typename FuncT,
+            typename ...Args
+        >
+        static auto
+        try_array (FuncT &&func, Args &&...args)
+        {
+            uint32_t expected = 0;
+            try_func (func, args..., &expected, nullptr);
+
+            using ResultT = std::remove_pointer_t<
+                std::tuple_element_t<
+                    sizeof...(Args) + 1,
+                    typename func_traits<FuncT>::argument_types
+                >
+            >;
+
+            ContainerT<ResultT> values (expected);
+            uint32_t found = 0;
+            try_func (func, args..., &found, std::data (values));
+            CHECK_EQ (expected, found);
+            return values;
+        }
     };