NAME

deductionguidesforstd::optional - deductionguidesforstd::optional

Synopsis

Defined in header <optional>
template<class T> (since C++17)
optional(T) -> optional<T>;

One deduction guide is provided for std::optional to account for the edge cases
missed by the implicit deduction guides, in particular, non-copyable arguments and
array to pointer conversion

Example

// Run this code

#include <optional>

int main()
{
int a[2];
std::optional oa{a}; // explicit deduction guide is used in this case
}