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deductionguidesforstd::optional(3) C++ Standard Libary deductionguidesforstd::optional(3)

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
}

2022.07.31 http://cppreference.com