forked from Research/WhisperCom
51 lines
984 B
Markdown
51 lines
984 B
Markdown
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# basic_json::is_number
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```cpp
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constexpr bool is_number() const noexcept;
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```
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This function returns `#!cpp true` if and only if the JSON value is a number. This includes both integer (signed and
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unsigned) and floating-point values.
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## Return value
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`#!cpp true` if type is number (regardless whether integer, unsigned integer or floating-type), `#!cpp false` otherwise.
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## Exception safety
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No-throw guarantee: this member function never throws exceptions.
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## Complexity
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Constant.
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## Possible implementation
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```cpp
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constexpr bool is_number() const noexcept
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{
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return is_number_integer() || is_number_float();
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}
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```
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## Example
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??? example
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The following code exemplifies `is_number()` for all JSON types.
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```cpp
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--8<-- "examples/is_number.cpp"
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```
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Output:
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```json
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--8<-- "examples/is_number.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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- Extended to also return `#!cpp true` for unsigned integers in 2.0.0.
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