Introduce HashQ<> and UnorderedMap<>

Invading into std:: is frowned upon, even though legitimate from the C++ standard perspective. Given that it's possible to pass a hash object to unordered_map, it only takes an alias for std::unordered_map to avoid having to specialize std::hash. And besides, a generic compatibility bridge between qHash and std::hash has been long needed.

std::hash<QString> in converters.h remains for now; it will be dropped separately when the API files get regenerated to use UnorderedMap.

1 files changed, 4 insertions, 10 deletions

diff --git a/lib/converters.h b/lib/converters.h
index 587e4544..b753a80b 100644
--- a/lib/converters.h
+++ b/lib/converters.h
@@ -28,16 +28,10 @@
 #include <QtCore/QUrlQuery>
 #include <QtCore/QVector>
 
-#include <unordered_map>
 #include <vector>
-#if 0 // Waiting for C++17
-#    include <experimental/optional>
-
-template <typename T>
-using optional = std::experimental::optional<T>;
-#endif
 
 // Enable std::unordered_map<QString, T>
+// REMOVEME in favor of UnorderedMap, once we regenerate API files
 namespace std {
 template <>
 struct hash<QString> {
@@ -296,9 +290,9 @@ struct HashMapFromJson {
     }
 };
 
-template <typename T>
-struct JsonObjectConverter<std::unordered_map<QString, T>>
-    : public HashMapFromJson<std::unordered_map<QString, T>> {};
+template <typename T, typename HashT>
+struct JsonObjectConverter<std::unordered_map<QString, T, HashT>>
+    : public HashMapFromJson<std::unordered_map<QString, T, HashT>> {};
 
 template <typename T>
 struct JsonObjectConverter<QHash<QString, T>>