This struct is used to implement direct initialization of the private data member of the std::optional class, which makes it possible to support immovable types returned from the transform member function.
Declared in <bslstl_optional.h>
template<
class t_TYPE,
class t_INVOCABLE,
class t_ARG>
struct Optional_ImmovableHelper;
| Name | Description |
|---|---|
operator t_TYPE | Invoke invocable with arg and return the result as t_TYPE. |
| Name | Description |
|---|---|
arg | argument forwarded to invocable |
invocable | callable invoked to produce the result |