From 182b32d807d7b6964c8f28fdd162f393e65f03b0 Mon Sep 17 00:00:00 2001 From: No Date: Mon, 22 May 2023 11:51:33 -0400 Subject: [PATCH 1/2] Use template get instead of get in examples https://github.com/nlohmann/json/issues/4038 --- README.md | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/README.md b/README.md index acc16eace6..ae2a4ad126 100644 --- a/README.md +++ b/README.md @@ -301,7 +301,7 @@ Note the difference between serialization and assignment: json j_string = "this is a string"; // retrieve the string value -auto cpp_string = j_string.get(); +auto cpp_string = j_string.template get(); // retrieve the string value (alternative when a variable already exists) std::string cpp_string2; j_string.get_to(cpp_string2); @@ -310,7 +310,7 @@ j_string.get_to(cpp_string2); std::string serialized_string = j_string.dump(); // output of original string -std::cout << cpp_string << " == " << cpp_string2 << " == " << j_string.get() << '\n'; +std::cout << cpp_string << " == " << cpp_string2 << " == " << j_string.template get() << '\n'; // output of serialized value std::cout << j_string << " == " << serialized_string << std::endl; ``` @@ -483,7 +483,7 @@ for (auto& element : j) { } // getter/setter -const auto tmp = j[0].get(); +const auto tmp = j[0].template get(); j[1] = 42; bool foo = j.at(2); @@ -691,7 +691,7 @@ You can switch off implicit conversions by defining `JSON_USE_IMPLICIT_CONVERSIO // strings std::string s1 = "Hello, world!"; json js = s1; -auto s2 = js.get(); +auto s2 = js.template get(); // NOT RECOMMENDED std::string s3 = js; std::string s4; @@ -700,7 +700,7 @@ s4 = js; // Booleans bool b1 = true; json jb = b1; -auto b2 = jb.get(); +auto b2 = jb.template get(); // NOT RECOMMENDED bool b3 = jb; bool b4; @@ -709,7 +709,7 @@ b4 = jb; // numbers int i = 42; json jn = i; -auto f = jn.get(); +auto f = jn.template get(); // NOT RECOMMENDED double f2 = jb; double f3; @@ -752,9 +752,9 @@ j["age"] = p.age; // convert from JSON: copy each value from the JSON object ns::person p { - j["name"].get(), - j["address"].get(), - j["age"].get() + j["name"].template get(), + j["address"].template get(), + j["age"].template get() }; ``` @@ -771,7 +771,7 @@ std::cout << j << std::endl; // {"address":"744 Evergreen Terrace","age":60,"name":"Ned Flanders"} // conversion: json -> person -auto p2 = j.get(); +auto p2 = j.template get(); // that's it assert(p == p2); @@ -798,13 +798,13 @@ namespace ns { ``` That's all! When calling the `json` constructor with your type, your custom `to_json` method will be automatically called. -Likewise, when calling `get()` or `get_to(your_type&)`, the `from_json` method will be called. +Likewise, when calling `template get()` or `get_to(your_type&)`, the `from_json` method will be called. Some important things: * Those methods **MUST** be in your type's namespace (which can be the global namespace), or the library will not be able to locate them (in this example, they are in namespace `ns`, where `person` is defined). * Those methods **MUST** be available (e.g., proper headers must be included) everywhere you use these conversions. Look at [issue 1108](https://github.com/nlohmann/json/issues/1108) for errors that may occur otherwise. -* When using `get()`, `your_type` **MUST** be [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible). (There is a way to bypass this requirement described later.) +* When using `template get()`, `your_type` **MUST** be [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible). (There is a way to bypass this requirement described later.) * In function `from_json`, use function [`at()`](https://json.nlohmann.me/api/basic_json/at/) to access the object values rather than `operator[]`. In case a key does not exist, `at` throws an exception that you can handle, whereas `operator[]` exhibits undefined behavior. * You do not need to add serializers or deserializers for STL types like `std::vector`: the library already implements these. @@ -889,8 +889,8 @@ namespace nlohmann { if (j.is_null()) { opt = boost::none; } else { - opt = j.get(); // same as above, but with - // adl_serializer::from_json + opt = j.template get(); // same as above, but with + // adl_serializer::from_json } } }; @@ -917,7 +917,7 @@ namespace nlohmann { // note: the return type is no longer 'void', and the method only takes // one argument static move_only_type from_json(const json& j) { - return {j.get()}; + return {j.template get()}; } // Here's the catch! You must provide a to_json method! Otherwise, you @@ -1021,11 +1021,11 @@ assert(j == "stopped"); // json string to enum json j3 = "running"; -assert(j3.get() == TS_RUNNING); +assert(j3.template get() == TS_RUNNING); // undefined json value to enum (where the first map entry above is the default) json jPi = 3.14; -assert(jPi.get() == TS_INVALID ); +assert(jPi.template get() == TS_INVALID ); ``` Just as in [Arbitrary Type Conversions](#arbitrary-types-conversions) above, @@ -1033,7 +1033,7 @@ Just as in [Arbitrary Type Conversions](#arbitrary-types-conversions) above, - It MUST be available (e.g., proper headers must be included) everywhere you use the conversions. Other Important points: -- When using `get()`, undefined JSON values will default to the first pair specified in your map. Select this default pair carefully. +- When using `template get()`, undefined JSON values will default to the first pair specified in your map. Select this default pair carefully. - If an enum or JSON value is specified more than once in your map, the first matching occurrence from the top of the map will be returned when converting to or from JSON. ### Binary formats (BSON, CBOR, MessagePack, UBJSON, and BJData) From f8a7f03f05a07f8b6f91065a591780a52b0afb48 Mon Sep 17 00:00:00 2001 From: tusooa Date: Mon, 22 May 2023 12:24:10 -0400 Subject: [PATCH 2/2] Replace all get<> with template get<> --- .../from_json__default_constructible.cpp | 2 +- .../from_json__non_default_constructible.cpp | 2 +- docs/examples/get__PointerType.cpp | 10 +++++----- docs/examples/get__ValueType_const.cpp | 16 ++++++++-------- ...nlohmann_define_type_intrusive_explicit.cpp | 4 ++-- .../nlohmann_define_type_intrusive_macro.cpp | 4 ++-- ...ne_type_intrusive_with_default_explicit.cpp | 4 ++-- ...efine_type_intrusive_with_default_macro.cpp | 4 ++-- ...mann_define_type_non_intrusive_explicit.cpp | 4 ++-- ...lohmann_define_type_non_intrusive_macro.cpp | 4 ++-- ...ype_non_intrusive_with_default_explicit.cpp | 4 ++-- ...e_type_non_intrusive_with_default_macro.cpp | 4 ++-- docs/examples/nlohmann_json_serialize_enum.cpp | 8 ++++---- .../nlohmann_json_serialize_enum_2.cpp | 4 ++-- .../docs/api/adl_serializer/from_json.md | 2 +- .../macros/json_disable_enum_serialization.md | 10 +++++----- .../macros/json_use_implicit_conversions.md | 2 +- .../api/macros/nlohmann_json_serialize_enum.md | 2 +- docs/mkdocs/docs/features/arbitrary_types.md | 18 +++++++++--------- docs/mkdocs/docs/features/enum_conversion.md | 6 +++--- .../docs/features/types/number_handling.md | 8 ++++---- .../mkdocs/docs/integration/migration_guide.md | 2 +- 22 files changed, 62 insertions(+), 62 deletions(-) diff --git a/docs/examples/from_json__default_constructible.cpp b/docs/examples/from_json__default_constructible.cpp index 17c0551c8c..07d71ac951 100644 --- a/docs/examples/from_json__default_constructible.cpp +++ b/docs/examples/from_json__default_constructible.cpp @@ -31,7 +31,7 @@ int main() j["address"] = "744 Evergreen Terrace"; j["age"] = 60; - auto p = j.get(); + auto p = j.template get(); std::cout << p.name << " (" << p.age << ") lives in " << p.address << std::endl; } diff --git a/docs/examples/from_json__non_default_constructible.cpp b/docs/examples/from_json__non_default_constructible.cpp index 6cb86153cc..ec8206eade 100644 --- a/docs/examples/from_json__non_default_constructible.cpp +++ b/docs/examples/from_json__non_default_constructible.cpp @@ -47,7 +47,7 @@ int main() j["address"] = "744 Evergreen Terrace"; j["age"] = 60; - auto p = j.get(); + auto p = j.template get(); std::cout << p.name << " (" << p.age << ") lives in " << p.address << std::endl; } diff --git a/docs/examples/get__PointerType.cpp b/docs/examples/get__PointerType.cpp index 2f32ed7af6..309c8deebb 100644 --- a/docs/examples/get__PointerType.cpp +++ b/docs/examples/get__PointerType.cpp @@ -9,11 +9,11 @@ int main() json value = 17; // explicitly getting pointers - auto p1 = value.get(); - auto p2 = value.get(); - auto p3 = value.get(); - auto p4 = value.get(); - auto p5 = value.get(); + auto p1 = value.template get(); + auto p2 = value.template get(); + auto p3 = value.template get(); + auto p4 = value.template get(); + auto p5 = value.template get(); // print the pointees std::cout << *p1 << ' ' << *p2 << ' ' << *p3 << ' ' << *p4 << '\n'; diff --git a/docs/examples/get__ValueType_const.cpp b/docs/examples/get__ValueType_const.cpp index 7a703aaeb1..db63791fcb 100644 --- a/docs/examples/get__ValueType_const.cpp +++ b/docs/examples/get__ValueType_const.cpp @@ -22,14 +22,14 @@ int main() }; // use explicit conversions - auto v1 = json_types["boolean"].get(); - auto v2 = json_types["number"]["integer"].get(); - auto v3 = json_types["number"]["integer"].get(); - auto v4 = json_types["number"]["floating-point"].get(); - auto v5 = json_types["number"]["floating-point"].get(); - auto v6 = json_types["string"].get(); - auto v7 = json_types["array"].get>(); - auto v8 = json_types.get>(); + auto v1 = json_types["boolean"].template get(); + auto v2 = json_types["number"]["integer"].template get(); + auto v3 = json_types["number"]["integer"].template get(); + auto v4 = json_types["number"]["floating-point"].template get(); + auto v5 = json_types["number"]["floating-point"].template get(); + auto v6 = json_types["string"].template get(); + auto v7 = json_types["array"].template get>(); + auto v8 = json_types.template get>(); // print the conversion results std::cout << v1 << '\n'; diff --git a/docs/examples/nlohmann_define_type_intrusive_explicit.cpp b/docs/examples/nlohmann_define_type_intrusive_explicit.cpp index 7d2ba8aa1f..f2d6812cb0 100644 --- a/docs/examples/nlohmann_define_type_intrusive_explicit.cpp +++ b/docs/examples/nlohmann_define_type_intrusive_explicit.cpp @@ -45,13 +45,13 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; try { - auto p3 = j3.get(); + auto p3 = j3.template get(); } catch (json::exception& e) { diff --git a/docs/examples/nlohmann_define_type_intrusive_macro.cpp b/docs/examples/nlohmann_define_type_intrusive_macro.cpp index 2977cd4568..9c020689b8 100644 --- a/docs/examples/nlohmann_define_type_intrusive_macro.cpp +++ b/docs/examples/nlohmann_define_type_intrusive_macro.cpp @@ -33,13 +33,13 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; try { - auto p3 = j3.get(); + auto p3 = j3.template get(); } catch (json::exception& e) { diff --git a/docs/examples/nlohmann_define_type_intrusive_with_default_explicit.cpp b/docs/examples/nlohmann_define_type_intrusive_with_default_explicit.cpp index 7400c47a87..0fb2e1cb21 100644 --- a/docs/examples/nlohmann_define_type_intrusive_with_default_explicit.cpp +++ b/docs/examples/nlohmann_define_type_intrusive_with_default_explicit.cpp @@ -46,10 +46,10 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; - auto p3 = j3.get(); + auto p3 = j3.template get(); std::cout << "roundtrip: " << json(p3) << std::endl; } diff --git a/docs/examples/nlohmann_define_type_intrusive_with_default_macro.cpp b/docs/examples/nlohmann_define_type_intrusive_with_default_macro.cpp index 851a3582f4..52668516b5 100644 --- a/docs/examples/nlohmann_define_type_intrusive_with_default_macro.cpp +++ b/docs/examples/nlohmann_define_type_intrusive_with_default_macro.cpp @@ -33,10 +33,10 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; - auto p3 = j3.get(); + auto p3 = j3.template get(); std::cout << "roundtrip: " << json(p3) << std::endl; } diff --git a/docs/examples/nlohmann_define_type_non_intrusive_explicit.cpp b/docs/examples/nlohmann_define_type_non_intrusive_explicit.cpp index b71613d4f6..b3040adc61 100644 --- a/docs/examples/nlohmann_define_type_non_intrusive_explicit.cpp +++ b/docs/examples/nlohmann_define_type_non_intrusive_explicit.cpp @@ -38,13 +38,13 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; try { - auto p3 = j3.get(); + auto p3 = j3.template get(); } catch (json::exception& e) { diff --git a/docs/examples/nlohmann_define_type_non_intrusive_macro.cpp b/docs/examples/nlohmann_define_type_non_intrusive_macro.cpp index be11a45767..2c76830d82 100644 --- a/docs/examples/nlohmann_define_type_non_intrusive_macro.cpp +++ b/docs/examples/nlohmann_define_type_non_intrusive_macro.cpp @@ -26,13 +26,13 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; try { - auto p3 = j3.get(); + auto p3 = j3.template get(); } catch (json::exception& e) { diff --git a/docs/examples/nlohmann_define_type_non_intrusive_with_default_explicit.cpp b/docs/examples/nlohmann_define_type_non_intrusive_with_default_explicit.cpp index 6b538d18d5..855ab52b85 100644 --- a/docs/examples/nlohmann_define_type_non_intrusive_with_default_explicit.cpp +++ b/docs/examples/nlohmann_define_type_non_intrusive_with_default_explicit.cpp @@ -44,10 +44,10 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; - auto p3 = j3.get(); + auto p3 = j3.template get(); std::cout << "roundtrip: " << json(p3) << std::endl; } diff --git a/docs/examples/nlohmann_define_type_non_intrusive_with_default_macro.cpp b/docs/examples/nlohmann_define_type_non_intrusive_with_default_macro.cpp index aa9bc53b4b..8c41c65ecd 100644 --- a/docs/examples/nlohmann_define_type_non_intrusive_with_default_macro.cpp +++ b/docs/examples/nlohmann_define_type_non_intrusive_with_default_macro.cpp @@ -31,10 +31,10 @@ int main() // deserialization: json -> person json j2 = R"({"address": "742 Evergreen Terrace", "age": 40, "name": "Homer Simpson"})"_json; - auto p2 = j2.get(); + auto p2 = j2.template get(); // incomplete deserialization: json j3 = R"({"address": "742 Evergreen Terrace", "name": "Maggie Simpson"})"_json; - auto p3 = j3.get(); + auto p3 = j3.template get(); std::cout << "roundtrip: " << json(p3) << std::endl; } diff --git a/docs/examples/nlohmann_json_serialize_enum.cpp b/docs/examples/nlohmann_json_serialize_enum.cpp index f9e472c64b..a40db49eaa 100644 --- a/docs/examples/nlohmann_json_serialize_enum.cpp +++ b/docs/examples/nlohmann_json_serialize_enum.cpp @@ -44,16 +44,16 @@ int main() // deserialization json j_running = "running"; json j_blue = "blue"; - auto running = j_running.get(); - auto blue = j_blue.get(); + auto running = j_running.template get(); + auto blue = j_blue.template get(); std::cout << j_running << " -> " << running << ", " << j_blue << " -> " << static_cast(blue) << std::endl; // deserializing undefined JSON value to enum // (where the first map entry above is the default) json j_pi = 3.14; - auto invalid = j_pi.get(); - auto unknown = j_pi.get(); + auto invalid = j_pi.template get(); + auto unknown = j_pi.template get(); std::cout << j_pi << " -> " << invalid << ", " << j_pi << " -> " << static_cast(unknown) << std::endl; } diff --git a/docs/examples/nlohmann_json_serialize_enum_2.cpp b/docs/examples/nlohmann_json_serialize_enum_2.cpp index fd27226ca9..b35e94cc56 100644 --- a/docs/examples/nlohmann_json_serialize_enum_2.cpp +++ b/docs/examples/nlohmann_json_serialize_enum_2.cpp @@ -26,8 +26,8 @@ int main() // deserialization json j_rot = "rot"; - auto rot = j_rot.get(); - auto red = j_red.get(); + auto rot = j_rot.template get(); + auto red = j_red.template get(); std::cout << j_rot << " -> " << static_cast(rot) << std::endl; std::cout << j_red << " -> " << static_cast(red) << std::endl; } diff --git a/docs/mkdocs/docs/api/adl_serializer/from_json.md b/docs/mkdocs/docs/api/adl_serializer/from_json.md index ba932e9e77..fa19c96f24 100644 --- a/docs/mkdocs/docs/api/adl_serializer/from_json.md +++ b/docs/mkdocs/docs/api/adl_serializer/from_json.md @@ -37,7 +37,7 @@ Copy of the JSON value, converted to `ValueType` ??? example "Example: (1) Default-constructible type" The example below shows how a `from_json` function can be implemented for a user-defined type. This function is - called by the `adl_serializer` when `get()` is called. + called by the `adl_serializer` when `template get()` is called. ```cpp --8<-- "examples/from_json__default_constructible.cpp" diff --git a/docs/mkdocs/docs/api/macros/json_disable_enum_serialization.md b/docs/mkdocs/docs/api/macros/json_disable_enum_serialization.md index 6df3dd5cb2..6440e34e32 100644 --- a/docs/mkdocs/docs/api/macros/json_disable_enum_serialization.md +++ b/docs/mkdocs/docs/api/macros/json_disable_enum_serialization.md @@ -53,7 +53,7 @@ The default value is `0`. const json j = Choice::first; // normally invokes from_json parse function but with JSON_DISABLE_ENUM_SERIALIZATION defined, it does not - Choice ch = j.get(); + Choice ch = j.template get(); } ``` @@ -86,7 +86,7 @@ The default value is `0`. const json j = Choice::first; // uses user-defined from_json function defined by macro - Choice ch = j.get(); + Choice ch = j.template get(); } ``` @@ -109,7 +109,7 @@ The default value is `0`. void from_json(const json& j, Choice& ch) { - auto value = j.get(); + auto value = j.template get(); if (value == "first") { ch = Choice::first; @@ -122,7 +122,7 @@ The default value is `0`. void to_json(json& j, const Choice& ch) { - auto value = j.get(); + auto value = j.template get(); if (value == "first") { ch = Choice::first; @@ -139,7 +139,7 @@ The default value is `0`. const json j = Choice::first; // uses user-defined from_json function - Choice ch = j.get(); + Choice ch = j.template get(); } ``` diff --git a/docs/mkdocs/docs/api/macros/json_use_implicit_conversions.md b/docs/mkdocs/docs/api/macros/json_use_implicit_conversions.md index adadffab6e..557dfa299e 100644 --- a/docs/mkdocs/docs/api/macros/json_use_implicit_conversions.md +++ b/docs/mkdocs/docs/api/macros/json_use_implicit_conversions.md @@ -46,7 +46,7 @@ By default, implicit conversions are enabled. ```cpp json j = "Hello, world!"; - auto s = j.get(); + auto s = j.template get(); ``` ## See also diff --git a/docs/mkdocs/docs/api/macros/nlohmann_json_serialize_enum.md b/docs/mkdocs/docs/api/macros/nlohmann_json_serialize_enum.md index c28765a8ce..dc2cc8ecb8 100644 --- a/docs/mkdocs/docs/api/macros/nlohmann_json_serialize_enum.md +++ b/docs/mkdocs/docs/api/macros/nlohmann_json_serialize_enum.md @@ -37,7 +37,7 @@ inline void from_json(const BasicJsonType& j, type& e); !!! important "Important notes" - - When using [`get()`](../basic_json/get.md), undefined JSON values will default to the first specified + - When using [`template get()`](../basic_json/get.md), undefined JSON values will default to the first specified conversion. Select this default pair carefully. See example 1 below. - If an enum or JSON value is specified in multiple conversions, the first matching conversion from the top of the list will be returned when converting to or from JSON. See example 2 below. diff --git a/docs/mkdocs/docs/features/arbitrary_types.md b/docs/mkdocs/docs/features/arbitrary_types.md index 046a597a31..9b54fcb3e8 100644 --- a/docs/mkdocs/docs/features/arbitrary_types.md +++ b/docs/mkdocs/docs/features/arbitrary_types.md @@ -24,9 +24,9 @@ j["age"] = p.age; // convert from JSON: copy each value from the JSON object ns::person p { - j["name"].get(), - j["address"].get(), - j["age"].get() + j["name"].template get(), + j["address"].template get(), + j["age"].template get() }; ``` @@ -43,7 +43,7 @@ std::cout << j << std::endl; // {"address":"744 Evergreen Terrace","age":60,"name":"Ned Flanders"} // conversion: json -> person -auto p2 = j.get(); +auto p2 = j.template get(); // that's it assert(p == p2); @@ -70,13 +70,13 @@ namespace ns { ``` That's all! When calling the `json` constructor with your type, your custom `to_json` method will be automatically called. -Likewise, when calling `get()` or `get_to(your_type&)`, the `from_json` method will be called. +Likewise, when calling `template get()` or `get_to(your_type&)`, the `from_json` method will be called. Some important things: * Those methods **MUST** be in your type's namespace (which can be the global namespace), or the library will not be able to locate them (in this example, they are in namespace `ns`, where `person` is defined). * Those methods **MUST** be available (e.g., proper headers must be included) everywhere you use these conversions. Look at [issue 1108](https://github.com/nlohmann/json/issues/1108) for errors that may occur otherwise. -* When using `get()`, `your_type` **MUST** be [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible). (There is a way to bypass this requirement described later.) +* When using `template get()`, `your_type` **MUST** be [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible). (There is a way to bypass this requirement described later.) * In function `from_json`, use function [`at()`](../api/basic_json/at.md) to access the object values rather than `operator[]`. In case a key does not exist, `at` throws an exception that you can handle, whereas `operator[]` exhibits undefined behavior. * You do not need to add serializers or deserializers for STL types like `std::vector`: the library already implements these. @@ -171,7 +171,7 @@ struct adl_serializer> { if (j.is_null()) { opt = boost::none; } else { - opt = j.get(); // same as above, but with + opt = j.template get(); // same as above, but with // adl_serializer::from_json } } @@ -204,7 +204,7 @@ namespace nlohmann { // note: the return type is no longer 'void', and the method only takes // one argument static move_only_type from_json(const json& j) { - return {j.get()}; + return {j.template get()}; } // Here's the catch! You must provide a to_json method! Otherwise, you @@ -268,7 +268,7 @@ struct bad_serializer static void to_json(const BasicJsonType& j, T& value) { // this calls BasicJsonType::json_serializer::from_json(j, value); // if BasicJsonType::json_serializer == bad_serializer ... oops! - value = j.template get(); // oops! + value = j.template template get(); // oops! } }; ``` diff --git a/docs/mkdocs/docs/features/enum_conversion.md b/docs/mkdocs/docs/features/enum_conversion.md index 59ffbd5f11..1755bca2ad 100644 --- a/docs/mkdocs/docs/features/enum_conversion.md +++ b/docs/mkdocs/docs/features/enum_conversion.md @@ -36,11 +36,11 @@ assert(j == "stopped"); // json string to enum json j3 = "running"; -assert(j3.get() == TS_RUNNING); +assert(j3.template get() == TS_RUNNING); // undefined json value to enum (where the first map entry above is the default) json jPi = 3.14; -assert(jPi.get() == TS_INVALID ); +assert(jPi.template get() == TS_INVALID ); ``` ## Notes @@ -54,7 +54,7 @@ Just as in [Arbitrary Type Conversions](arbitrary_types.md) above, Other Important points: -- When using `get()`, undefined JSON values will default to the first pair specified in your map. Select this +- When using `template get()`, undefined JSON values will default to the first pair specified in your map. Select this default pair carefully. - If an enum or JSON value is specified more than once in your map, the first matching occurrence from the top of the map will be returned when converting to or from JSON. diff --git a/docs/mkdocs/docs/features/types/number_handling.md b/docs/mkdocs/docs/features/types/number_handling.md index 03d8c9c693..c457ae07c0 100644 --- a/docs/mkdocs/docs/features/types/number_handling.md +++ b/docs/mkdocs/docs/features/types/number_handling.md @@ -235,9 +235,9 @@ integers, and between integers and floating-point values to integers. This beha !!! warning "Unconditional number conversions" ```cpp hl_lines="3" - double d = 42.3; // non-integer double value 42.3 - json jd = d; // stores double value 42.3 - std::int64_t i = jd.get(); // now i==42; no warning or error is produced + double d = 42.3; // non-integer double value 42.3 + json jd = d; // stores double value 42.3 + std::int64_t i = jd.template get(); // now i==42; no warning or error is produced ``` Note the last line with throw a [`json.exception.type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) @@ -259,7 +259,7 @@ The rationale is twofold: if (jd.is_number_integer()) { // if so, do the conversion and use i - std::int64_t i = jd.get(); + std::int64_t i = jd.template get(); // ... } else diff --git a/docs/mkdocs/docs/integration/migration_guide.md b/docs/mkdocs/docs/integration/migration_guide.md index 69dc7eca91..d250f5b20b 100644 --- a/docs/mkdocs/docs/integration/migration_guide.md +++ b/docs/mkdocs/docs/integration/migration_guide.md @@ -187,7 +187,7 @@ conversions with calls to [`get`](../api/basic_json/get.md), [`get_to`](../api/b ```cpp nlohmann::json j = "Hello, world!"; - auto s = j.get(); + auto s = j.template get(); ``` === "Future-proof (alternative)"