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Niels Lohmann
d04f78864c
- API pages for set and push_back of basic_json_document and for the editable aliases; the class overviews name the Editable parameter - type_error.319 on the exceptions page - the feature page explains editing, and the examples show when it helps: a configuration file changed without reformatting it Signed-off-by: Niels Lohmann <mail@nlohmann.me>
31 lines
1.1 KiB
C++
31 lines
1.1 KiB
C++
#include <iostream>
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#include <nlohmann/json_view.hpp>
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using json = nlohmann::json;
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using json_editable_document = nlohmann::json_editable_document;
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using json_editable_view = nlohmann::json_editable_view;
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int main()
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{
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// a configuration file, as it might be read from disk
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const std::string text = R"({"name": "cache", "host": "db1", "port": 6379, "price": 19.90})";
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std::cout << text << "\n\n";
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// patch two fields -- "price" is never touched
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json_editable_document doc = json_editable_document::parse(text);
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doc.set(doc.root(), "host", "db2");
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doc.set(doc.root(), "retries", 3);
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// member order (the new member at the end) and the untouched number's
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// exact spelling survive
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std::cout << doc.root().dump(-1, ' ', false, json_editable_view::number_format::source) << '\n';
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// the same patch on a plain json value: keys are sorted (object_t is a
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// std::map), and "price" is rewritten even though the patch never
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// touched it
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json plain = json::parse(text);
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plain["host"] = "db2";
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plain["retries"] = 3;
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std::cout << plain.dump() << '\n';
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}
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