At 2025-05-20 19:48:03, "Jens Maurer" <jens.maurer@gmx.net> wrote:
>
>This says "draft".  Is there a paper anywhere?
>
>Have you reviewed the pending pattern matching proposal(s),
>such as https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p2688r5.html ?
>
>Thanks,
>Jens
>
>
>On 20/05/2025 13.38, Zhao YunShan via Std-Proposals wrote:
>> 
>>     In C++, the |switch| statement is a fundamental control-flow construct originally designed to work only with integer types (|int|, |char|, |enum|, etc.). However, in real-world development, programmers often need to handle string-based (|std::string|) branching logic. While the standard syntax does not natively support strings, well-structured design patterns can still leverage |switch|-like behavior to replace lengthy |if...else if| chains, significantly improving code readability and conciseness.
>> 
>> #include<iostream>
>> #include<string>
>> int main()
>> {
>>     std::string router;
>>     switch (router)
>>     {
>>     case "cpp":
>>         std::cout << "cpp router selected.";
>>         break;
>>     case "hpp":
>>         std::cout << "hpp router selected.";
>>         break;
>>     default:
>>         std::cout << "Unknown router type.";
>>         break;
>>     }
>>     return 0;
>> }
>> 
>> 
>> By leveraging compile-time static analysis, |switch| statements can be optimized into various efficient data structures:
>> *
>> *
>> *    Jump tables* for few cases,
>> *    Balanced binary search* for many branches,
>> *    Hash tables* where supported.
>> 
>> This ensures optimal time complexity (*O(1)* to *O(log n)*) even with large branch sets.
>> 
>>