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[std-proposals] Addition of std::contains to Simplify Container Value Checks

From: Robert Sitton <robert.sitton_at_[hidden]>
Date: Sat, 23 Dec 2023 03:20:46 -0600
Dear std-proposals community,

I hope this email finds you well. I am writing to introduce a proposal for
the addition of a new utility function, std::contains, to the C++ standard
library. This function aims to streamline the common task of checking
whether a container contains a specific element and enhance the overall
readability of C++ code.

One of the frequent operations in C++ programming involves checking whether
a container (e.g., std::vector, std::list, std::set) contains a particular
value. While C++ provides mechanisms to achieve this, such as custom loops
or std::find, these approaches may not always be as intuitive and efficient
as desired.

Proposal Overview:
The proposed std::contains function is designed to simplify this operation
and make code more expressive. It offers a straightforward and concise way
to check if a container contains a specified element, reducing the need for
manual iterations and enhancing code clarity.

Function Signature:
template <typename Container, typename T>
bool std::contains(const Container& container, const T& value);

Example Usage:
std::vector<int> numbers = {1, 2, 3, 4, 5};
bool containsThree = std::contains(numbers, 3); // true
bool containsTen = std::contains(numbers, 10); // false
bool containsOne = std::contains(numbers, {1, 4, 5}); // true
bool containsTwo = std::contains(numbers, {7, 8}); // false

Your Feedback:
I would greatly appreciate your feedback and insights on this proposal.
Before formally submitting it to the C++ committee, I believe it is
essential to gather input from the community to ensure that the proposal
aligns with the needs and expectations of C++ developers.

Please feel free to share your thoughts, suggestions, or concerns regarding
the proposed std::contains function. Your expertise and feedback are
invaluable in refining and improving this idea. Thank you for your time and
attention. I look forward to engaging in constructive discussions and
working together to enhance the C++ standard library.



Received on 2023-12-23 09:21:24