constexpr bool has_subtype() const noexcept;
Returns whether the value has a subtype.
whether the value has a subtype
No-throw guarantee: this function never throws exceptions.
Constant.
??? example
The example below demonstrates how `has_subtype` can check whether a subtype was set. ```cpp --8<-- "examples/byte_container_with_subtype__has_subtype.cpp" ``` Output: ```json --8<-- "examples/byte_container_with_subtype__has_subtype.output" ```
Since version 3.8.0.