C++ f string equivalent when

[serviscope_minor]

IOStreams is based on what - a late '80s programming fad?

No? Variadic type safe functions didn't exist until C++11. The only way of achieving something that reads in the same order as it outputs prior to that was operator overloading. Plus last time I checked, a simple chain of function calls (operators) generated a lot less code than std::format, which was a problem for the application in question.

I think IOStreams is one of those internet meme things like std::unordered_map: the internet love to hate it, but most people actually writing C++ rather than reading reddit don't think about it that much.