spdlog VS STL

Why a new lib instead of using or contributing to an existing one as spdlog?

https://github.com/gabime/spdlog

GitHub repo: gabime/spdlog

SpdLog https://github.com/gabime/spdlog

The usual recommendation when logging libraries are brought up is spdlog, which is however header-only. It's available on Conan-center.

* Aha! In digging up the docs for NDC, I found this[1], which does mention a book for your reading list: "Patterns for Logging Diagnostic Messages" part of the book "Pattern Languages of Program Design 3" edited by Martin et al.

[1] https://github.com/gabime/spdlog

FetchContent_Declare( spdlog GIT_REPOSITORY https://github.com/gabime/spdlog GIT_TAG origin/v1.x ) FetchContent_MakeAvailable(spdlog)

Typically, you'd use a logging library to handle stuff like this. I personally like spdlog. You use different logger functions (info, warn, error) and depending on what level you have set for the logger (or globally) some of the functions become no-ops. E.g. When not running in verbose mode all spdlog::info() do nothing.

Again, they are barely functional.

MSVC chokes on many standard-defined constructs: https://github.com/microsoft/STL/issues/1694

clang does not claim to be "mostly usable" at all - most papers are not implemented: https://clang.llvm.org/cxx_status.html#cxx20

And gcc will only start ot be usable with CMake when version 14 is released - that has not happened yet.

And, as I mentioned before, IDE support is either buggy (Visual Studio) or non-existing (any other IDE/OS). So you're off to writing in a text editor and hoping your compiler works to a somewhat usable degree. Yes, at some point people should start using modules, I agree, but to advise library maintainers to ship modularized code... the tooling just isn't there yet.

I mean, the GitHub issue is Microsoft trying to ship their standard library modularized, they employ some of the most capable folks on the planet and pay them big money to get that done, while metaphorically sitting next to the Microsoft compiler devs, and they barely, barely get it done (with bugs, as they themselves mention). This is too much for most other library maintainers.

Notice that there are in practice three distinct implementations of the C++ standard library. They're all awful to read though, here's Microsoft's std::vector https://github.com/microsoft/STL/blob/main/stl/inc/vector

However you're being slightly unfair because Rust's Vec is just defined (opaquely) as a RawVec plus a length value, so let's link RawVec, https://doc.rust-lang.org/src/alloc/raw_vec.rs.html -- RawVec is the part responsible for the messy problem of how to actually implement the growable array type.

Still, the existence of three C++ libraries with slightly different (or sometimes hugely different) quality of implementation means good C++ code can't depend on much beyond what the ISO document promises, and yet it must guard against the nonsense inflicted by all three and by lacks of the larger language. In particular everything must use the reserved prefix so that it's not smashed inadvertently by a macro, and lots of weird C++ idioms that preserve performance by sacrificing clarity of implementation are needed, even where you'd ordinarily sacrifice to get the development throughput win of everybody know what's going on. For example you'll see a lot of "pair" types bought into existence which are there to squirrel away a ZST that in C++ can't exist, using the Empty Base Optimisation. In Rust the language has ZSTs so they can just write what they meant.

Here is Microsoft's implementation of map in the standard library. I think of myself as a competent programmer / computer scientist. I couldn't write this: https://github.com/microsoft/STL/blob/f392449fb72d1a387ac502...

Be careful on Windows, the MSVC STL implementation uses the system time, so it can be badly impacted by clock adjustments: https://github.com/microsoft/STL/issues/718

Can you provide a link? If it affects import std;, I'd like to add it to my tracking issue.

Do you have a list of the bugs you've filed and their current status, like the one I have for the STL? I saw you mentioned 3 bugs 7 months ago, 2 of which were fixed in 17.6 and the third of which was a duplicate of an active bug ("deducing this" is known to not yet work with modules, which is why we don't define the feature-test macro to claim full support).

Yep. And look at our implementation's name: https://github.com/microsoft/STL