[catblast01]

I think I addressed that: “how they’re organized in the spec”. They’re distinct, but outside of internal references in the spec the distinction between language and library doesn’t really matter. To a user of C++ it’s all one spec with distinctions for freestanding and hosted implementations, etc. You can’t have a conformant C++ implementation without elements from both.

The original point of this thread was about where std::format exists and from a implementation point of view it doesn’t really matter.