Observers

`error_type &&assume_error() && noexcept`

Narrow contract rvalue reference observer of the stored error. NoValuePolicy::narrow_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs unless NoValuePolicy::narrow_error_check() does that. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::narrow_error_check(). Guarantees: An exception is never thrown. »

`error_type &&assume_error() && noexcept`

Narrow contract rvalue reference observer of the stored error. NoValuePolicy::narrow_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs unless NoValuePolicy::narrow_error_check() does that. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::narrow_error_check(). Guarantees: An exception is never thrown. »

`error_type &&error() &&`

Wide contract rvalue reference observer of the stored error. NoValuePolicy::wide_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs if NoValuePolicy::wide_error_check() returns. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::wide_error_check(). Guarantees: None. »

`error_type &&error() &&`

Wide contract rvalue reference observer of the stored error. NoValuePolicy::wide_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs if NoValuePolicy::wide_error_check() returns. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::wide_error_check(). Guarantees: None. »

`error_type &assume_error() & noexcept`

Narrow contract lvalue reference observer of the stored error. NoValuePolicy::narrow_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs unless NoValuePolicy::narrow_error_check() does that. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::narrow_error_check(). Guarantees: An exception is never thrown. »

`error_type &assume_error() & noexcept`

Narrow contract lvalue reference observer of the stored error. NoValuePolicy::narrow_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs unless NoValuePolicy::narrow_error_check() does that. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::narrow_error_check(). Guarantees: An exception is never thrown. »

`error_type &error() &`

Wide contract lvalue reference observer of the stored error. NoValuePolicy::wide_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs if NoValuePolicy::wide_error_check() returns. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::wide_error_check(). Guarantees: None. »

`error_type &error() &`

Wide contract lvalue reference observer of the stored error. NoValuePolicy::wide_error_check() is first invoked, then the reference to the error is returned. As a valid default constructed error is always present, no undefined behaviour occurs if NoValuePolicy::wide_error_check() returns. Note that if error_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::wide_error_check(). Guarantees: None. »

`exception_type &&assume_exception() && noexcept`

Narrow contract rvalue reference observer of the stored exception. NoValuePolicy::narrow_exception_check() is first invoked, then the reference to the exception is returned. As a valid default constructed exception is always present, no undefined behaviour occurs unless NoValuePolicy::narrow_exception_check() does that. Note that if exception_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::narrow_exception_check(). Guarantees: An exception is never thrown. »

`exception_type &&exception() &&`

Wide contract rvalue reference observer of the stored exception. NoValuePolicy::wide_exception_check() is first invoked, then the reference to the exception is returned. As a valid default constructed exception is always present, no undefined behaviour occurs if NoValuePolicy::wide_exception_check() returns. Note that if exception_type is void, only a const overload returning void is present. Requires: Always available. Complexity: Depends on NoValuePolicy::wide_exception_check(). Guarantees: None. »