diff --git a/include/nlohmann/adl_serializer.hpp b/include/nlohmann/adl_serializer.hpp
index 53c9009f0b..54e9aac6b7 100644
--- a/include/nlohmann/adl_serializer.hpp
+++ b/include/nlohmann/adl_serializer.hpp
@@ -20,8 +20,10 @@ struct adl_serializer
     @param[in,out] val  value to write to
     */
     template<typename BasicJsonType, typename ValueType>
-    static void from_json(BasicJsonType&& j, ValueType& val) noexcept(
-        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
+    static auto from_json(BasicJsonType&& j, ValueType& val) noexcept(
+        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val))) -> decltype(
+            ::nlohmann::from_json(std::forward<BasicJsonType>(j), val)
+        )
     {
         ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
     }
@@ -35,9 +37,11 @@ struct adl_serializer
     @param[in,out] j  JSON value to write to
     @param[in] val     value to read from
     */
-    template<typename BasicJsonType, typename ValueType>
-    static void to_json(BasicJsonType& j, ValueType&& val) noexcept(
+    template <typename BasicJsonType, typename ValueType>
+    static auto to_json(BasicJsonType& j, ValueType&& val) noexcept(
         noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val))))
+    -> decltype(::nlohmann::to_json(j, std::forward<ValueType>(val)),
+                void())
     {
         ::nlohmann::to_json(j, std::forward<ValueType>(val));
     }
diff --git a/include/nlohmann/detail/conversions/from_json.hpp b/include/nlohmann/detail/conversions/from_json.hpp
index 5956352fb9..2375d0660b 100644
--- a/include/nlohmann/detail/conversions/from_json.hpp
+++ b/include/nlohmann/detail/conversions/from_json.hpp
@@ -127,16 +127,6 @@ void from_json(const BasicJsonType& j, EnumType& e)
     e = static_cast<EnumType>(val);
 }
 
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::array_t& arr)
-{
-    if (JSON_UNLIKELY(not j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
-    }
-    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
-}
-
 // forward_list doesn't have an insert method
 template<typename BasicJsonType, typename T, typename Allocator,
          enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
@@ -166,24 +156,28 @@ void from_json(const BasicJsonType& j, std::valarray<T>& l)
     std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l));
 }
 
-template<typename BasicJsonType, typename CompatibleArrayType>
-void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<0> /*unused*/)
+template<typename BasicJsonType>
+void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
 {
-    using std::end;
+    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
+}
 
-    std::transform(j.begin(), j.end(),
-                   std::inserter(arr, end(arr)), [](const BasicJsonType & i)
+template <typename BasicJsonType, typename T, std::size_t N>
+auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
+                          priority_tag<2> /*unused*/)
+-> decltype(j.template get<T>(), void())
+{
+    for (std::size_t i = 0; i < N; ++i)
     {
-        // get<BasicJsonType>() returns *this, this won't call a from_json
-        // method when value_type is BasicJsonType
-        return i.template get<typename CompatibleArrayType::value_type>();
-    });
+        arr[i] = j.at(i).template get<T>();
+    }
 }
 
 template<typename BasicJsonType, typename CompatibleArrayType>
 auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<1> /*unused*/)
 -> decltype(
     arr.reserve(std::declval<typename CompatibleArrayType::size_type>()),
+    j.template get<typename CompatibleArrayType::value_type>(),
     void())
 {
     using std::end;
@@ -198,25 +192,34 @@ auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, prio
     });
 }
 
-template<typename BasicJsonType, typename T, std::size_t N>
-void from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr, priority_tag<2> /*unused*/)
+template <typename BasicJsonType, typename CompatibleArrayType>
+void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr,
+                          priority_tag<0> /*unused*/)
 {
-    for (std::size_t i = 0; i < N; ++i)
+    using std::end;
+
+    std::transform(
+        j.begin(), j.end(), std::inserter(arr, end(arr)),
+        [](const BasicJsonType & i)
     {
-        arr[i] = j.at(i).template get<T>();
-    }
+        // get<BasicJsonType>() returns *this, this won't call a from_json
+        // method when value_type is BasicJsonType
+        return i.template get<typename CompatibleArrayType::value_type>();
+    });
 }
 
-template <
-    typename BasicJsonType, typename CompatibleArrayType,
-    enable_if_t <
-        is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and
-        not std::is_same<typename BasicJsonType::array_t,
-                         CompatibleArrayType>::value and
-        std::is_constructible <
-            BasicJsonType, typename CompatibleArrayType::value_type >::value,
-        int > = 0 >
-void from_json(const BasicJsonType& j, CompatibleArrayType& arr)
+template <typename BasicJsonType, typename CompatibleArrayType,
+          enable_if_t <
+              is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_basic_json<CompatibleArrayType>::value,
+              int > = 0 >
+
+auto from_json(const BasicJsonType& j, CompatibleArrayType& arr)
+-> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
+j.template get<typename CompatibleArrayType::value_type>(),
+void())
 {
     if (JSON_UNLIKELY(not j.is_array()))
     {
@@ -224,7 +227,7 @@ void from_json(const BasicJsonType& j, CompatibleArrayType& arr)
                                       std::string(j.type_name())));
     }
 
-    from_json_array_impl(j, arr, priority_tag<2> {});
+    from_json_array_impl(j, arr, priority_tag<3> {});
 }
 
 template<typename BasicJsonType, typename CompatibleObjectType,
@@ -347,35 +350,13 @@ void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyE
 
 struct from_json_fn
 {
-  private:
     template<typename BasicJsonType, typename T>
-    auto call(const BasicJsonType& j, T& val, priority_tag<1> /*unused*/) const
+    auto operator()(const BasicJsonType& j, T& val) const
     noexcept(noexcept(from_json(j, val)))
     -> decltype(from_json(j, val), void())
     {
         return from_json(j, val);
     }
-
-    template<typename BasicJsonType, typename T>
-    void call(const BasicJsonType& /*unused*/, T& /*unused*/, priority_tag<0> /*unused*/) const noexcept
-    {
-        static_assert(sizeof(BasicJsonType) == 0,
-                      "could not find from_json() method in T's namespace");
-#ifdef _MSC_VER
-        // MSVC does not show a stacktrace for the above assert
-        using decayed = uncvref_t<T>;
-        static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0,
-                      "forcing MSVC stacktrace to show which T we're talking about.");
-#endif
-    }
-
-  public:
-    template<typename BasicJsonType, typename T>
-    void operator()(const BasicJsonType& j, T& val) const
-    noexcept(noexcept(std::declval<from_json_fn>().call(j, val, priority_tag<1> {})))
-    {
-        return call(j, val, priority_tag<1> {});
-    }
 };
 }
 
diff --git a/include/nlohmann/detail/conversions/to_json.hpp b/include/nlohmann/detail/conversions/to_json.hpp
index 04c93be199..8f2bd2660c 100644
--- a/include/nlohmann/detail/conversions/to_json.hpp
+++ b/include/nlohmann/detail/conversions/to_json.hpp
@@ -252,7 +252,8 @@ template <typename BasicJsonType, typename CompatibleArrayType,
           enable_if_t<is_compatible_array_type<BasicJsonType,
                       CompatibleArrayType>::value and
                       not is_compatible_object_type<
-                          BasicJsonType, CompatibleArrayType>::value,
+                          BasicJsonType, CompatibleArrayType>::value and
+                      not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value,
                       int> = 0>
 void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
 {
@@ -285,9 +286,12 @@ void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
     external_constructor<value_t::object>::construct(j, std::move(obj));
 }
 
-template<typename BasicJsonType, typename T, std::size_t N,
-         enable_if_t<not std::is_constructible<typename BasicJsonType::string_t, T (&)[N]>::value, int> = 0>
-void to_json(BasicJsonType& j, T (&arr)[N])
+template <
+    typename BasicJsonType, typename T, std::size_t N,
+    enable_if_t<not std::is_constructible<typename BasicJsonType::string_t,
+                const T (&)[N]>::value,
+                int> = 0 >
+void to_json(BasicJsonType& j, const T (&arr)[N])
 {
     external_constructor<value_t::array>::construct(j, arr);
 }
@@ -320,35 +324,12 @@ void to_json(BasicJsonType& j, const std::tuple<Args...>& t)
 
 struct to_json_fn
 {
-  private:
     template<typename BasicJsonType, typename T>
-    auto call(BasicJsonType& j, T&& val, priority_tag<1> /*unused*/) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
+    auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
     -> decltype(to_json(j, std::forward<T>(val)), void())
     {
         return to_json(j, std::forward<T>(val));
     }
-
-    template<typename BasicJsonType, typename T>
-    void call(BasicJsonType& /*unused*/, T&& /*unused*/, priority_tag<0> /*unused*/) const noexcept
-    {
-        static_assert(sizeof(BasicJsonType) == 0,
-                      "could not find to_json() method in T's namespace");
-
-#ifdef _MSC_VER
-        // MSVC does not show a stacktrace for the above assert
-        using decayed = uncvref_t<T>;
-        static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0,
-                      "forcing MSVC stacktrace to show which T we're talking about.");
-#endif
-    }
-
-  public:
-    template<typename BasicJsonType, typename T>
-    void operator()(BasicJsonType& j, T&& val) const
-    noexcept(noexcept(std::declval<to_json_fn>().call(j, std::forward<T>(val), priority_tag<1> {})))
-    {
-        return call(j, std::forward<T>(val), priority_tag<1> {});
-    }
 };
 }
 
diff --git a/include/nlohmann/detail/meta/type_traits.hpp b/include/nlohmann/detail/meta/type_traits.hpp
index 39ef6f7545..0383472b17 100644
--- a/include/nlohmann/detail/meta/type_traits.hpp
+++ b/include/nlohmann/detail/meta/type_traits.hpp
@@ -127,9 +127,6 @@ struct is_compatible_array_type_impl <
     is_detected<iterator_t, CompatibleArrayType>::value >>
 {
     static constexpr auto value = not(
-                                      is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value or
-                                      std::is_constructible<typename BasicJsonType::string_t,
-                                      CompatibleArrayType>::value or
                                       is_basic_json_nested_type<BasicJsonType, CompatibleArrayType>::value);
 };
 
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index ab3a13cdfc..0b4d46022f 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -484,9 +484,6 @@ struct is_compatible_array_type_impl <
     is_detected<iterator_t, CompatibleArrayType>::value >>
 {
     static constexpr auto value = not(
-                                      is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value or
-                                      std::is_constructible<typename BasicJsonType::string_t,
-                                      CompatibleArrayType>::value or
                                       is_basic_json_nested_type<BasicJsonType, CompatibleArrayType>::value);
 };
 
@@ -1121,16 +1118,6 @@ void from_json(const BasicJsonType& j, EnumType& e)
     e = static_cast<EnumType>(val);
 }
 
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::array_t& arr)
-{
-    if (JSON_UNLIKELY(not j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
-    }
-    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
-}
-
 // forward_list doesn't have an insert method
 template<typename BasicJsonType, typename T, typename Allocator,
          enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
@@ -1160,24 +1147,28 @@ void from_json(const BasicJsonType& j, std::valarray<T>& l)
     std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l));
 }
 
-template<typename BasicJsonType, typename CompatibleArrayType>
-void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<0> /*unused*/)
+template<typename BasicJsonType>
+void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
 {
-    using std::end;
+    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
+}
 
-    std::transform(j.begin(), j.end(),
-                   std::inserter(arr, end(arr)), [](const BasicJsonType & i)
+template <typename BasicJsonType, typename T, std::size_t N>
+auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
+                          priority_tag<2> /*unused*/)
+-> decltype(j.template get<T>(), void())
+{
+    for (std::size_t i = 0; i < N; ++i)
     {
-        // get<BasicJsonType>() returns *this, this won't call a from_json
-        // method when value_type is BasicJsonType
-        return i.template get<typename CompatibleArrayType::value_type>();
-    });
+        arr[i] = j.at(i).template get<T>();
+    }
 }
 
 template<typename BasicJsonType, typename CompatibleArrayType>
 auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<1> /*unused*/)
 -> decltype(
     arr.reserve(std::declval<typename CompatibleArrayType::size_type>()),
+    j.template get<typename CompatibleArrayType::value_type>(),
     void())
 {
     using std::end;
@@ -1192,25 +1183,34 @@ auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, prio
     });
 }
 
-template<typename BasicJsonType, typename T, std::size_t N>
-void from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr, priority_tag<2> /*unused*/)
+template <typename BasicJsonType, typename CompatibleArrayType>
+void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr,
+                          priority_tag<0> /*unused*/)
 {
-    for (std::size_t i = 0; i < N; ++i)
+    using std::end;
+
+    std::transform(
+        j.begin(), j.end(), std::inserter(arr, end(arr)),
+        [](const BasicJsonType & i)
     {
-        arr[i] = j.at(i).template get<T>();
-    }
+        // get<BasicJsonType>() returns *this, this won't call a from_json
+        // method when value_type is BasicJsonType
+        return i.template get<typename CompatibleArrayType::value_type>();
+    });
 }
 
-template <
-    typename BasicJsonType, typename CompatibleArrayType,
-    enable_if_t <
-        is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and
-        not std::is_same<typename BasicJsonType::array_t,
-                         CompatibleArrayType>::value and
-        std::is_constructible <
-            BasicJsonType, typename CompatibleArrayType::value_type >::value,
-        int > = 0 >
-void from_json(const BasicJsonType& j, CompatibleArrayType& arr)
+template <typename BasicJsonType, typename CompatibleArrayType,
+          enable_if_t <
+              is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value and
+              not is_basic_json<CompatibleArrayType>::value,
+              int > = 0 >
+
+auto from_json(const BasicJsonType& j, CompatibleArrayType& arr)
+-> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
+j.template get<typename CompatibleArrayType::value_type>(),
+void())
 {
     if (JSON_UNLIKELY(not j.is_array()))
     {
@@ -1218,7 +1218,7 @@ void from_json(const BasicJsonType& j, CompatibleArrayType& arr)
                                       std::string(j.type_name())));
     }
 
-    from_json_array_impl(j, arr, priority_tag<2> {});
+    from_json_array_impl(j, arr, priority_tag<3> {});
 }
 
 template<typename BasicJsonType, typename CompatibleObjectType,
@@ -1341,35 +1341,13 @@ void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyE
 
 struct from_json_fn
 {
-  private:
     template<typename BasicJsonType, typename T>
-    auto call(const BasicJsonType& j, T& val, priority_tag<1> /*unused*/) const
+    auto operator()(const BasicJsonType& j, T& val) const
     noexcept(noexcept(from_json(j, val)))
     -> decltype(from_json(j, val), void())
     {
         return from_json(j, val);
     }
-
-    template<typename BasicJsonType, typename T>
-    void call(const BasicJsonType& /*unused*/, T& /*unused*/, priority_tag<0> /*unused*/) const noexcept
-    {
-        static_assert(sizeof(BasicJsonType) == 0,
-                      "could not find from_json() method in T's namespace");
-#ifdef _MSC_VER
-        // MSVC does not show a stacktrace for the above assert
-        using decayed = uncvref_t<T>;
-        static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0,
-                      "forcing MSVC stacktrace to show which T we're talking about.");
-#endif
-    }
-
-  public:
-    template<typename BasicJsonType, typename T>
-    void operator()(const BasicJsonType& j, T& val) const
-    noexcept(noexcept(std::declval<from_json_fn>().call(j, val, priority_tag<1> {})))
-    {
-        return call(j, val, priority_tag<1> {});
-    }
 };
 }
 
@@ -1770,7 +1748,8 @@ template <typename BasicJsonType, typename CompatibleArrayType,
           enable_if_t<is_compatible_array_type<BasicJsonType,
                       CompatibleArrayType>::value and
                       not is_compatible_object_type<
-                          BasicJsonType, CompatibleArrayType>::value,
+                          BasicJsonType, CompatibleArrayType>::value and
+                      not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value,
                       int> = 0>
 void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
 {
@@ -1803,9 +1782,12 @@ void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
     external_constructor<value_t::object>::construct(j, std::move(obj));
 }
 
-template<typename BasicJsonType, typename T, std::size_t N,
-         enable_if_t<not std::is_constructible<typename BasicJsonType::string_t, T (&)[N]>::value, int> = 0>
-void to_json(BasicJsonType& j, T (&arr)[N])
+template <
+    typename BasicJsonType, typename T, std::size_t N,
+    enable_if_t<not std::is_constructible<typename BasicJsonType::string_t,
+                const T (&)[N]>::value,
+                int> = 0 >
+void to_json(BasicJsonType& j, const T (&arr)[N])
 {
     external_constructor<value_t::array>::construct(j, arr);
 }
@@ -1838,35 +1820,12 @@ void to_json(BasicJsonType& j, const std::tuple<Args...>& t)
 
 struct to_json_fn
 {
-  private:
     template<typename BasicJsonType, typename T>
-    auto call(BasicJsonType& j, T&& val, priority_tag<1> /*unused*/) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
+    auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
     -> decltype(to_json(j, std::forward<T>(val)), void())
     {
         return to_json(j, std::forward<T>(val));
     }
-
-    template<typename BasicJsonType, typename T>
-    void call(BasicJsonType& /*unused*/, T&& /*unused*/, priority_tag<0> /*unused*/) const noexcept
-    {
-        static_assert(sizeof(BasicJsonType) == 0,
-                      "could not find to_json() method in T's namespace");
-
-#ifdef _MSC_VER
-        // MSVC does not show a stacktrace for the above assert
-        using decayed = uncvref_t<T>;
-        static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0,
-                      "forcing MSVC stacktrace to show which T we're talking about.");
-#endif
-    }
-
-  public:
-    template<typename BasicJsonType, typename T>
-    void operator()(BasicJsonType& j, T&& val) const
-    noexcept(noexcept(std::declval<to_json_fn>().call(j, std::forward<T>(val), priority_tag<1> {})))
-    {
-        return call(j, std::forward<T>(val), priority_tag<1> {});
-    }
 };
 }
 
@@ -11128,8 +11087,10 @@ struct adl_serializer
     @param[in,out] val  value to write to
     */
     template<typename BasicJsonType, typename ValueType>
-    static void from_json(BasicJsonType&& j, ValueType& val) noexcept(
-        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
+    static auto from_json(BasicJsonType&& j, ValueType& val) noexcept(
+        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val))) -> decltype(
+            ::nlohmann::from_json(std::forward<BasicJsonType>(j), val)
+        )
     {
         ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
     }
@@ -11143,9 +11104,11 @@ struct adl_serializer
     @param[in,out] j  JSON value to write to
     @param[in] val     value to read from
     */
-    template<typename BasicJsonType, typename ValueType>
-    static void to_json(BasicJsonType& j, ValueType&& val) noexcept(
+    template <typename BasicJsonType, typename ValueType>
+    static auto to_json(BasicJsonType& j, ValueType&& val) noexcept(
         noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val))))
+    -> decltype(::nlohmann::to_json(j, std::forward<ValueType>(val)),
+                void())
     {
         ::nlohmann::to_json(j, std::forward<ValueType>(val));
     }