json/docs/examples/contains__json_pointer.cpp
Ivor Wanders e5fb288b90 Capture exceptions by const& in docs.
Performed with:
```
find ./ -type f -name *.cpp -print0 | xargs -0 sed -i -e 's|catch (json|catch (const json|g'
```
2023-08-04 11:38:56 -04:00

44 lines
1.1 KiB
C++

#include <iostream>
#include <nlohmann/json.hpp>
using json = nlohmann::json;
using namespace nlohmann::literals;
int main()
{
// create a JSON value
json j =
{
{"number", 1}, {"string", "foo"}, {"array", {1, 2}}
};
std::cout << std::boolalpha
<< j.contains("/number"_json_pointer) << '\n'
<< j.contains("/string"_json_pointer) << '\n'
<< j.contains("/array"_json_pointer) << '\n'
<< j.contains("/array/1"_json_pointer) << '\n'
<< j.contains("/array/-"_json_pointer) << '\n'
<< j.contains("/array/4"_json_pointer) << '\n'
<< j.contains("/baz"_json_pointer) << std::endl;
try
{
// try to use an array index with leading '0'
j.contains("/array/01"_json_pointer);
}
catch (const json::parse_error& e)
{
std::cout << e.what() << '\n';
}
try
{
// try to use an array index that is not a number
j.contains("/array/one"_json_pointer);
}
catch (const json::parse_error& e)
{
std::cout << e.what() << '\n';
}
}