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https://github.com/nlohmann/json.git
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Niels Lohmann
08dcdaf9b8
- API pages for operator[], at, front, back, find, contains, count, begin, end, cbegin, cend, items, and type_name of basic_json_view, linked both ways with the basic_json pages - the feature page and size() describe document order and duplicate keys - the examples show when the view helps: reading a few fields of a large text, probing optional members, and members in source order Signed-off-by: Niels Lohmann <mail@nlohmann.me>
37 lines
1.0 KiB
C++
37 lines
1.0 KiB
C++
#include <iostream>
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#include <nlohmann/json_view.hpp>
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using json_document = nlohmann::json_document;
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using json_view = nlohmann::json_view;
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int main()
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{
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// required fields of a service configuration -- at() reports a missing
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// or wrong-typed field with the very same exception basic_json::at()
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// would throw for the equivalent nlohmann::json value, so error
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// handling written against basic_json::at() keeps working unchanged
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json_document config = json_document::parse(R"({"name": "cache", "port": "6379"})");
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const json_view service = config.root();
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std::cout << service.at("port").materialize().dump() << '\n';
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try
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{
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// "port" is a string, not an array
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static_cast<void>(service.at("port").at(0));
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}
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catch (const nlohmann::json::type_error& e)
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{
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std::cout << e.what() << '\n';
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}
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try
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{
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static_cast<void>(service.at("timeout"));
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}
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catch (const nlohmann::json::out_of_range& e)
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{
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std::cout << e.what() << '\n';
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}
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}
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