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- 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>
26 lines
855 B
C++
26 lines
855 B
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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int main()
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{
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// the same build log; back() reads only the final status. It is linear
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// in the number of events (unlike front(), which is constant), but
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// still far less work than materializing the whole array
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json_document log = json_document::parse(R"(["queued", "started", "compiling", "linking", "done"])");
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std::cout << log.root().back().materialize().dump() << '\n';
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// an empty log -- back() throws instead of the undefined behavior
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// basic_json::back() has for an empty array
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json_document empty_log = json_document::parse("[]");
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try
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{
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static_cast<void>(empty_log.root().back());
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}
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catch (const nlohmann::json::invalid_iterator& 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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