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59 lines
1.1 KiB
Markdown
59 lines
1.1 KiB
Markdown
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# basic_json::clear
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```cpp
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void clear() noexcept;
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```
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Clears the content of a JSON value and resets it to the default value as if [`basic_json(value_t)`](basic_json.md) would
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have been called with the current value type from [`type()`](type.md):
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Value type | initial value
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----------- | -------------
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null | `null`
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boolean | `false`
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string | `""`
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number | `0`
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binary | An empty byte vector
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object | `{}`
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array | `[]`
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Has the same effect as calling
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```.cpp
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*this = basic_json(type());
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```
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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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Linear in the size of the JSON value.
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## Notes
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All iterators, pointers and references related to this container are invalidated.
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## Example
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??? example
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The example below shows the effect of `clear()` to different
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JSON types.
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```cpp
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--8<-- "examples/clear.cpp"
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```
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Output:
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```json
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--8<-- "examples/clear.output"
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```
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## Version history
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- Added in version 1.0.0.
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- Added support for binary types in version 3.8.0.
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