[libcxx-commits] [libcxx] [libc++] Optimize std::find for segmented iterators (PR #67224)

[Louis Dionne via libcxx-commits]

================
@@ -126,6 +170,7 @@ TEST_CONSTEXPR_CXX20 bool test() {
 }
 
 int main(int, char**) {
+  test_deque();
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ldionne wrote:

I would like to have a test for the constexpr-ness of the new code path you are adding. You can either do that by creating your own segmented iterator container that is constexpr-friendly, or by using something like `join_view`, which should satisfy that criteria.

Actually, you should start by writing the test and notice that

```
_InputIterator operator()(_InputIterator __first, _InputIterator __last, _Proj& __proj)
```

is missing `constexpr`, which means that this wouldn't work right now :)

https://github.com/llvm/llvm-project/pull/67224