std::expected::emplace(3)

💖 NAME 💖

okay bestie, this is std::expected::emplace from the C++ Standard Libary — and the name is literally std::expected::emplace minus std::expected::emplace. iconic repetition, no notes 💅✨

✨ Synopsis ✨

T is not cv void:

template< class... Args >
constexpr T& emplace( Args&&... args ) noexcept;

• (1) since C++23

template< class U, class... Args >
constexpr T& emplace( std::initializer_list<U> il, Args&&... args ) noexcept;

• (2) since C++23

T is cv void:

constexpr void emplace() noexcept;

• (3) since C++23

Constructs an expected value in-place. After the call, has_value() returns true. 🫶

1. Destroys the contained value, then initializes the expected value contained in *this as if by direct-initializing an object of type T from the arguments std::forward<Args>(args)....

This overload participates in overload resolution only if std::is_nothrow_constructible_v<T, Args...> is true.

2. Destroys the contained value, then initializes the expected value contained in *this as if by direct-initializing an object of type T from the arguments il and std::forward<Args>(args)....

This overload participates in overload resolution only if std::is_nothrow_constructible_v<T, std::initializer_list<U>&, Args...> is true.

3. If *this contains an unexpected value, destroys that value.

🎀 Parameters 🎀

• args — the arguments to pass to the constructor
• il — the initializer list to pass to the constructor

🫶 Return value 🫶

• 1,2) A reference to the new contained value.
• 3) (none)

🧚 Notes 🧚

If the construction of T is potentially-throwing, this function is not defined. In this case, it is the responsibility of the user to create a temporary object and move or copy it. 🫡

🌈 Example 🌈

This section is incomplete Reason: no example

👑 See also 👑

• operator= — assigns contents (public member function)

🍓 Category 🍓

• * Todo no example

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that’s the whole page, bestie 💖 source: http://cppreference.com, version/date: 2024.06.10, page: std::expected::emplace(3) 🫶💅