[COFF] Re: C with Improvements :-)

On Mon, Jun 23, 2025 at 9:36 AM Douglas McIlroy &lt;douglas.mcilroy(a)dartmouth.edu&gt; wrote: Thank you for this interesting historical note, Doug. Personally, I've never found the `<<` or `>>` syntax troubling when using C++ IO streams, and the type safety is a notable improvement over printf/scanf et al. What I _do_ find troubling is that the stream itself is a stateful, mutable object, so to perform any sort of non-trivial formatting, one has to inject special control messages into the stream using the same syntax; these do compose (usually), but they're persistent, are overly verbose, and cumbersome to use in practice. Here, the concision of printf's "little language" of formatting verbs is superior, and far more readable. It seems obvious in retrospect that C++ would have been better off if augmented with a small hierarchy of "formatting objects" that encoded the various formatting directives, exposing a printf-like language, as a constructor argument, along with the datum. The stream would consume these for the purposes of formatting that specific datum, but then discard them, as opposed to holding onto whatever state they induced. Google eventually did something like this, which kinda-sorta made it out in the `absl::StrFormat` library, but it took far too long (and Google, for many years, explicitly forbade using iostreams in C++ code for dubious reasons). More recent languages have introduced happy mediums. I personally like the way that Rust handles this; `println!` is a macro, and interprets the format string at compile time, ensuring whatever it specifies matches its arguments vis types, visibility, safety, etc. But at the call site, it resembles the concision of printf via a small formatting language. - Dan C.