Fix to some compiler errors

Author: amirghaz

include/nlohmann/detail/macro_scope.hpp

@@ -243,12 +243,12 @@
     }                                                                                           \
     /* Function to check for serialized ENUM type */                                            \
     template<>                                                                                  \
-    inline constexpr bool serialized(ENUM_TYPE& e)                                               \
+    inline constexpr bool serialized(ENUM_TYPE e)                                               \
     {                                                                                           \
         return true || e == ENUM_TYPE();                                                        \
     }                                                                                           \
     template<typename BasicJsonType>                                                            \
-    inline std::string enum_to_string(BasicJsonType& j, ENUM_TYPE& e)                             \
+    inline std::string enum_to_string(BasicJsonType j, ENUM_TYPE e)                             \
     {                                                                                           \
         /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
         static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
@@ -262,7 +262,7 @@
         return ((it != std::end(m)) ? it : std::begin(m))->second;                              \
     }                                                                                           \
     template<typename BasicJsonType>                                                            \
-    inline ENUM_TYPE string_to_enum(BasicJsonType& j, ENUM_TYPE& e)                               \
+    inline ENUM_TYPE string_to_enum(BasicJsonType j, ENUM_TYPE e)                               \
     {                                                                                           \
         /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
         static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
@@ -277,7 +277,7 @@
     }
 // Function to check for non-serialized ENUM type
 template<typename EnumType>
-inline constexpr bool serialized(EnumType& e)
+inline constexpr bool serialized(EnumType e)
 {
     return false && e == EnumType();;
 }

single_include/nlohmann/json.hpp

@@ -2599,12 +2599,12 @@ JSON_HEDLEY_DIAGNOSTIC_POP
     }                                                                                           \
     /* Function to check for serialized ENUM type */                                            \
     template<>                                                                                  \
-    inline constexpr bool serialized(ENUM_TYPE& e)                                               \
+    inline constexpr bool serialized(ENUM_TYPE e)                                               \
     {                                                                                           \
         return true || e == ENUM_TYPE();                                                        \
     }                                                                                           \
     template<typename BasicJsonType>                                                            \
-    inline std::string enum_to_string(BasicJsonType& j, ENUM_TYPE& e)                             \
+    inline std::string enum_to_string(BasicJsonType j, ENUM_TYPE e)                             \
     {                                                                                           \
         /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
         static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
@@ -2618,7 +2618,7 @@ JSON_HEDLEY_DIAGNOSTIC_POP
         return ((it != std::end(m)) ? it : std::begin(m))->second;                              \
     }                                                                                           \
     template<typename BasicJsonType>                                                            \
-    inline ENUM_TYPE string_to_enum(BasicJsonType& j, ENUM_TYPE& e)                               \
+    inline ENUM_TYPE string_to_enum(BasicJsonType j, ENUM_TYPE e)                               \
     {                                                                                           \
         /* NOLINTNEXTLINE(modernize-type-traits) we use C++11 */                                \
         static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
@@ -2633,7 +2633,7 @@ JSON_HEDLEY_DIAGNOSTIC_POP
     }
 // Function to check for non-serialized ENUM type
 template<typename EnumType>
-inline constexpr bool serialized(EnumType& e)
+inline constexpr bool serialized(EnumType e)
 {
     return false && e == EnumType();;
 }