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nlohmann
85 lines
1.7 KiB
Markdown
85 lines
1.7 KiB
Markdown
# to_string(basic_json)
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```
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template <typename BasicJsonType>
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std::string to_string(const BasicJsonType& j);
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```
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This function implements a user-defined to_string for JSON objects.
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## Template parameters
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`BasicJsonType` : a specialization of [`basic_json`](https://json.nlohmann.me/api/basic_json/index.md)
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## Return value
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string containing the serialization of the JSON value
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## Exception safety
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Strong guarantee: if an exception is thrown, there are no changes to any JSON value.
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## Exceptions
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Throws [`type_error.316`](https://json.nlohmann.me/home/exceptions/#jsonexceptiontype_error316) if a string stored inside the JSON value is not UTF-8 encoded
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## Complexity
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Linear.
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## Possible implementation
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```
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template <typename BasicJsonType>
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std::string to_string(const BasicJsonType& j)
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{
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return j.dump();
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}
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```
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## Examples
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Example
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The following code shows how the library's `to_string()` function integrates with others, allowing argument-dependent lookup.
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```
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#include <iostream>
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#include <nlohmann/json.hpp>
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using json = nlohmann::json;
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using std::to_string;
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int main()
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{
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// create values
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json j = {{"one", 1}, {"two", 2}};
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int i = 42;
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// use ADL to select best to_string function
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auto j_str = to_string(j); // calling nlohmann::to_string
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auto i_str = to_string(i); // calling std::to_string
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// serialize without indentation
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std::cout << j_str << "\n\n"
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<< i_str << std::endl;
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}
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```
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Output:
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```
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{"one":1,"two":2}
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42
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```
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## See also
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- [dump](https://json.nlohmann.me/api/basic_json/dump/index.md)
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- [Serialization](https://json.nlohmann.me/features/serialization/index.md) - the serialization article
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## Version history
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Added in version 3.7.0.
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