std::flat_map::at(3)

🎀 std::flat_map::at(3) — C++ Standard Libary 🎀

okay bestie, this is the group-chat translation of the std::flat_map::at page, and yes we are keeping every single detail because facts are the main character 💅

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🌸 NAME 🌸

std::flat_map::at — std::flat_map::at

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🦋 Synopsis 🦋

T& at( const Key& key );             (1) (since C++23)
const T& at( const Key& key ) const; (2) (since C++23)
template< class K >                  (3) (since C++23)
T& at( const K& x );
template< class K >                  (4) (since C++23)
const T& at( const K& x ) const;

okay so this function returns a reference to the mapped value of the element with specified key ✨. If no such element exists, an exception of type std::out_of_range is thrown 😭.

• 1,2) — The key is equivalent to key.
• 3,4) — The key compares equivalent to the value x. The reference to the mapped value is obtained as if by expression this->find(x)->second.
• The expression this->find(x) must be well-formed and have well-defined behavior, otherwise the behavior is undefined 🚨. Like, do not play with undefined behavior, bestie.
• These overloads participate in overload resolution only if the qualified-id Compare::is_transparent is valid and denotes a type. It allows calling this function without constructing an instance of Key.

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🍓 Parameters 🍓

• key — the key of the element to find
• x — a value of any type that can be transparently compared with a key

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💖 Return value 💖

A reference to the mapped value of the requested element. It’s giving “here is your reference” energy 🫶.

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💀 Exceptions 💀

• 1,2) — std::out_of_range if the container does not have an element with the specified key.
• 3,4) — std::out_of_range if the container does not have the specified element, that is, if find(x) == end() is true.

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🔥 Complexity 🔥

Logarithmic in the size of the container. No cap, that’s the complexity 🧚.

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🧚 Example 🧚

This section is incomplete.

Reason: no example.

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🌈 See also 🌈

• operator[] — access or insert specified element (public member function)

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👑 Category 👑

• Todo no example

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Source/version/date sign-off: http://cppreference.com, 2024.06.10, std::flat_map::at(3) — mwah, bestie 💋✨