Open
Description
In C++ 11, it seems that a try / catch is the only way of achieving optional values. This works with singular JSON objects, but as soon as they are included in a JSON array, the optional-ness fails and is the NVP becomes required for all objects in the array. Is there any workaround for this use case?
Code to reproduce:
#include "cereal/archives/json.hpp"
#include "cereal/cereal.hpp"
#include "cereal/types/vector.hpp"
#include "gtest/gtest.h"
class foo
{
public:
size_t number {0};
bool optional {true};
template<class Archive>
void serialize(Archive &ar)
{
ar(CEREAL_NVP(number));
// Optional Overrides
try {
ar(CEREAL_NVP(optional));
}
catch (...){
std::cout << "Skipping optional" << std::endl;
}
}
};
class bar{
public:
std::vector<foo> foos;
template<class Archive>
void serialize(Archive &ar)
{
ar(CEREAL_NVP(foos));
}
};
TEST(ARR_TEST, test) {
// passes
const std::string foo_str = R"({
"test": {"number":1}
})";
foo f;
{
std::istringstream is(foo_str);
cereal::JSONInputArchive archive(is);
archive(f);
}
EXPECT_EQ(f.number, 1);
EXPECT_TRUE(f.optional);
// fails
const std::string bar_str = R"({
"test": {
"foos": [{"number":1}, {"number": 2}]
}
})";
bar b;
{
std::istringstream is(bar_str);
cereal::JSONInputArchive archive(is);
archive(b);
}
EXPECT_EQ(b.foos.size(), 2);
}Metadata
Metadata
Assignees
Labels
No labels