cling VS patterns

More recent activity, but based on clang: https://github.com/jupyter-xeus/xeus-cling https://github.com/root-project/cling

> The repl driven workflow is amazing and the lisp images are rock solid and highly performant.

do people not realize that basically everything vm/interpreted language has a repl these days?

https://www.digitalocean.com/community/tutorials/java-repl-j...

https://github.com/waf/CSharpRepl

https://pub.dev/packages/interactive

not to mention ruby, python, php, lua

hell even c++ has a janky repl https://github.com/root-project/cling

Interactive C++ with Cling, https://blog.llvm.org/posts/2020-11-30-interactive-cpp-with-cling/, https://github.com/root-project/cling/, Relaxing the One Definition Rule in Interpreted C++, https://dl.acm.org/doi/10.1145/3377555.3377901 (PDF: https://www.researchgate.net/publication/339463915_Relaxing_the_one_definition_rule_in_interpreted_C)

Want to see your mind blown? Check out cling, a (sort of) C and C++ interpreter (it's a REPL). Or the work in progress, live-developed clauf, a real C interpreter.

Cling: https://github.com/root-project/cling

Wanting to just test pure c or c++ functions that are hardware independent -> (solution that I'm using): cling just in time compiler, gives a shell that you can just experiment with C++ expressions

C++ source cannot contain a shebang, but you can make them executable with binfmt-misc, and have the kernel pass them to a C++ interpreter such as Cling upon execution. Pretty much the same as running Python or Bash scripts.

std::visit, std::holds_alternative, std::get, ... and this library disagree with you.

I agree, good syntax makes it better, and even with something pretty good by C++ standards Rust still feels a lot less busy (interestingly the library I linked is the precursor to a candidate for addition to C++23).

mpark/patterns

What? C++ will get pattern matching even later than python (C++23)

Match...case is not a replacement to switch statements. It's something called Pattern Matching. It's pretty common in functional languages (Haskell had pattern matching since forever) but it's becoming more mainstream nowadays. Rust has pattern matching and there are proposals to add pattern matching to C++ and JavaScript.

The variant approach was chosen with half an eye towards the pattern matching proposal. For example:

So is this just a copy of https://github.com/mpark/patterns or what?

What C++ does not do but Rust does, is functional-style pattern matching of these options, as seen in languages like Scala (2004), Haskell (1990) and Standard ML (1983) since seemingly forever. Worth noting is that there are some pretty impressive libraries out there that does this for C++ too, and it's currently a proposal for C++23.