[libcxx-commits] [libcxx] [libc++] P3168R2 Give std::optional Range Support (PR #146491)

[Nikolas Klauser via libcxx-commits]

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@@ -187,6 +200,8 @@ namespace std {
 #  include <__concepts/invocable.h>
 #  include <__config>
 #  include <__exception/exception.h>
+#  include <__format/format_context.h>
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philnik777 wrote:

Why is this include needed?

https://github.com/llvm/llvm-project/pull/146491