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nlohmann
77 lines
1.2 KiB
Markdown
77 lines
1.2 KiB
Markdown
# std::swap\<basic_json>
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```
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namespace std {
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void swap(nlohmann::basic_json& j1, nlohmann::basic_json& j2);
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}
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```
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Exchanges the values of two JSON objects.
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## Parameters
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`j1` (in, out) : value to be replaced by `j2`
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`j2` (in, out) : value to be replaced by `j1`
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## Exception safety
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No-throw guarantee: this function never throws exceptions.
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## Complexity
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Constant.
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## Possible implementation
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```
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void swap(nlohmann::basic_json& j1, nlohmann::basic_json& j2)
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{
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j1.swap(j2);
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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 two values are swapped with `std::swap`.
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```
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#include <iostream>
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#include <iomanip>
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#include <nlohmann/json.hpp>
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using json = nlohmann::json;
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int main()
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{
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// create JSON values
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json j1 = {{"one", 1}, {"two", 2}};
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json j2 = {1, 2, 4, 8, 16};
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std::cout << "j1 = " << j1 << " | j2 = " << j2 << '\n';
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// swap values
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std::swap(j1, j2);
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std::cout << "j1 = " << j1 << " | j2 = " << j2 << std::endl;
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}
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```
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Output:
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```
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j1 = {"one":1,"two":2} | j2 = [1,2,4,8,16]
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j1 = [1,2,4,8,16] | j2 = {"one":1,"two":2}
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```
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## See also
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- [swap](https://json.nlohmann.me/api/basic_json/swap/index.md)
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## Version history
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- Added in version 1.0.0.
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- Extended for arbitrary basic_json types in version 3.10.5.
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