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📝 cleanup

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This commit is contained in:
Niels Lohmann 2017-01-24 14:45:32 +01:00
parent daf8dcdb32
commit 781fd09f2d
1 changed files with 13 additions and 11 deletions
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README.md
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@ -449,6 +449,7 @@ Every type can be serialized in JSON, not just STL-containers and scalar types.
```cpp ```cpp
namespace ns { namespace ns {
// a simple struct to model a person
struct person { struct person {
std::string name; std::string name;
std::string address; std::string address;
@ -456,7 +457,7 @@ namespace ns {
}; };
} }
// convert to JSON // convert to JSON: copy each value into the JSON object
json j; json j;
ns::person p = createSomeone(); ns::person p = createSomeone();
j["name"] = p.name; j["name"] = p.name;
@ -465,7 +466,7 @@ j["age"] = p.age;
// ... // ...
// convert from JSON // convert from JSON: copy each value from the JSON object
ns::person p { ns::person p {
j["name"].get<std::string>(), j["name"].get<std::string>(),
j["address"].get<std::string>(), j["address"].get<std::string>(),
@ -476,9 +477,11 @@ ns::person p {
It works, but that's quite a lot of boilerplate... Hopefully, there's a better way: It works, but that's quite a lot of boilerplate... Hopefully, there's a better way:
```cpp ```cpp
// person -> json
ns::person p = createPerson(); ns::person p = createPerson();
json j = p; json j = p;
// json -> person
auto p2 = j.get<ns::person>(); auto p2 = j.get<ns::person>();
assert(p == p2); assert(p == p2);
``` ```
@ -547,9 +550,8 @@ namespace nlohmann {
if (opt == boost::none) { if (opt == boost::none) {
j = nullptr; j = nullptr;
} else { } else {
j = *opt; // this will call adl_serializer<T>::to_json j = *opt; // this will call adl_serializer<T>::to_json which will
// which will find the free function to_json // find the free function to_json in T's namespace!
// in T's namespace!
} }
} }
@ -581,15 +583,15 @@ struct move_only_type {
namespace nlohmann { namespace nlohmann {
template <> template <>
struct adl_serializer<move_only_type> { struct adl_serializer<move_only_type> {
// note: the return type is no longer 'void', // note: the return type is no longer 'void', and the method only takes
// and the method only takes one argument // one argument
static move_only_type from_json(const json& j) { static move_only_type from_json(const json& j) {
return {j.get<int>()}; return {j.get<int>()};
} }
// Here's the catch! You must provide a to_json method! // Here's the catch! You must provide a to_json method! Otherwise you
// Otherwise you will not be able to convert move_only_type to json, // will not be able to convert move_only_type to json, since you fully
// since you fully specialized adl_serializer on that type // specialized adl_serializer on that type
static void to_json(json& j, move_only_type t) { static void to_json(json& j, move_only_type t) {
j = t.i; j = t.i;
} }
@ -599,7 +601,7 @@ namespace nlohmann {
#### Can I write my own serializer? (Advanced use) #### Can I write my own serializer? (Advanced use)
Yes. You might want to take a look at `[unit-udt.cpp](https://github.com/nlohmann/json/blob/develop/test/src/unit-udt.cpp)` in the test suite, to see a few examples. Yes. You might want to take a look at [`unit-udt.cpp`](https://github.com/nlohmann/json/blob/develop/test/src/unit-udt.cpp) in the test suite, to see a few examples.
If you write your own serializer, you'll need to do a few things: If you write your own serializer, you'll need to do a few things: