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65 lines
1.6 KiB
Markdown
65 lines
1.6 KiB
Markdown
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# basic_json::get_ref
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```cpp
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template<typename ReferenceType>
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ReferenceType get_ref();
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template<typename ReferenceType>
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const ReferenceType get_ref() const;
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```
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Implicit reference access to the internally stored JSON value. No copies are made.
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## Template arguments
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`ReferenceType`
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: reference type; must be a reference to [`array_t`](array_t.md), [`object_t`](object_t.md),
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[`string_t`](string_t.md), [`boolean_t`](boolean_t.md), [`number_integer_t`](number_integer_t.md), or
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[`number_unsigned_t`](number_unsigned_t.md), [`number_float_t`](number_float_t.md), or [`binary_t`](binary_t.md).
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Enforced by static assertion.
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## Return value
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reference to the internally stored JSON value if the requested reference type fits to the JSON value; throws
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[`type_error.303`](../../home/exceptions.md#jsonexceptiontype_error303) otherwise
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## Exception safety
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Strong exception safety: if an exception occurs, the original value stays intact.
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## Exceptions
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Throws [`type_error.303`](../../home/exceptions.md#jsonexceptiontype_error303) if the requested reference type does not
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match the stored JSON value type; example: `"incompatible ReferenceType for get_ref, actual type is binary"`.
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## Complexity
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Constant.
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## Notes
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!!! warning
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Writing data to the referee of the result yields an undefined state.
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## Example
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??? example
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The example shows several calls to `get_ref()`.
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```cpp
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--8<-- "examples/get_ref.cpp"
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```
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Output:
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```json
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--8<-- "examples/get_ref.output"
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```
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## Version history
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- Added in version 1.1.0.
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- Extended to binary types in version 3.8.0.
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