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59 lines
1.5 KiB
Markdown
59 lines
1.5 KiB
Markdown
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# basic_json::get_to
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```cpp
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template<typename ValueType>
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ValueType& get_to(ValueType& v) const noexcept(
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noexcept(JSONSerializer<ValueType>::from_json(
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std::declval<const basic_json_t&>(), v)))
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```
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Explicit type conversion between the JSON value and a compatible value. The value is filled into the input parameter by
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calling the `json_serializer<ValueType>` `from_json()` method.
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The function is equivalent to executing
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```cpp
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ValueType v;
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JSONSerializer<ValueType>::from_json(*this, v);
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```
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This overloads is chosen if:
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- `ValueType` is not `basic_json`,
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- `json_serializer<ValueType>` has a `from_json()` method of the form `void from_json(const basic_json&, ValueType&)`
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## Template parameters
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`ValueType`
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: the value type to return
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## Return value
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the input parameter, allowing chaining calls
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## Exceptions
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Depends on what `json_serializer<ValueType>` `from_json()` method throws
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## Example
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??? example
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The example below shows several conversions from JSON values to other types. There a few things to note: (1)
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Floating-point numbers can be converted to integers, (2) A JSON array can be converted to a standard
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`#!cpp std::vector<short>`, (3) A JSON object can be converted to C++ associative containers such as
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`#cpp std::unordered_map<std::string, json>`.
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```cpp
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--8<-- "examples/get_to.cpp"
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```
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Output:
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```json
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--8<-- "examples/get_to.output"
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```
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## Version history
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- Since version 3.3.0.
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