PEGTL VS parser-demo

Very cool, and I like the name!

I'd be interested in reading about how Matcheroni compares with PEGTL and Lexy.

https://github.com/taocpp/PEGTL

I found a library I wanted to test: Pegtl

I like PEGTL

Sure - libraries that are expected to be entirely self-contained. The one that comes to mind is PEGTL, a parser combinator library that is intended to be embedded inside a larger program. Making it import more dependencies would break this philosophy. Similarly, in the Rust world, there are a variety of "no-std" crates that should be able to be imported even if the standard library is not available on the target platform.

The program in the post was just an example meant to illustrate the problem. Originally, this (new) behavior of MSVC broke my code in the PEGTL, see [this commit](https://github.com/taocpp/PEGTL/commit/e3c8cb499dc3d1d76d23f2d5d79469dcb15550c5) that I needed to apply to fix it.

As a professional C++ programmer I feel a lot of the reasons C++ gets this response is because it's simply not "batteries included" like Go or Rust.

C++ is a very powerful, unopinionated language, that gives you a lot of freedom to attack your problem domain the way you best see fit.

If you're writing a networked application, don't use POSIX sockets, go and find a higher level library. If you're parsing complex text formats, don't iterate over buffers with char*'s, go pick up PEGTL[0]. If you're working on graphs, or need to properly index in-memory data, go pick up Boost[1][2]. If you need a GUI, go pick up Qt.

It's extremely common in C++, due to the lack of a universal package management solution, for people to try and "muddle through" and do shit themselves when it's far outside their core competency.

At one of my last employers, the core product was parsing JSON with std::regex, simply because they couldn't be bothered to integrate a JSON library.

[0] https://github.com/taocpp/PEGTL

[1] https://www.boost.org/doc/libs/1_76_0/libs/graph/

[2] https://www.boost.org/doc/libs/1_76_0/libs/multi_index/doc/i...

You are looking for Boost.Spirit (https://www.boost.org/doc/libs/1_76_0/libs/spirit/doc/x3/html/index.html) or PEGTL (https://github.com/taocpp/PEGTL)

I personally prefer to use parsing combinator libraries in C++, where the "grammar" is just part of normal C++ and directly integrate. Examples are Boost.Spirit, pegtl, or (my own) lexy.

While I'm not quite sure how this might transfer to your approach, with your Haskell-inspired style being quite different from our C++ templates, in the PEGTL our equivalent to your Char, which is called one, is variadic (true to the T in PEGTL a variadic template) and takes a list of possible matches.

I have a demo project that fixes a lot of the default insanities.

I have an old demo project that demonstrates most of that for flex/bison, but this is C/C++ oriented so might not be super applicable for you.

It's just unfortunate that flex and bison have bad defaults due to historical compatibility with lex and yacc. If you're using them I have a demo project that tweaks the defaults toward sanity, though I haven't updated it for recent warnings.

I made a demo project that ties them together. I'm pretty sure at least one of the fixes was due to header cycle problems, but I haven't touched it for a while. (note also that the demo was fully warning-clean at the time, but there may be new warnings since)

I made a demo project that avoids several historical annoyances with Flex and Bison - in particular, I made it warnings-clean (though I haven't updated it recently), and I avoid global state.

I have a demo project that enables all of the non-default options that you really should be using in all new projects. Note that the demo doesn't demonstrate meaningful grammars, just shows how to arrange the surrounding code and makefile.

I have a demo project that twiddles most of the important knobs.

Bash is a really complicated language. Redirections and such are simple; they are just tokenization, and any lexer/parser tutorial should get you there (I have a demo project using flex/bison).

Bison can be configured to avoid every single one of those problems. I use reentrant versions (both with and without push parsing) in my demo project. I admit I didn't bother with named references or cleaning up after errors.

a lot of the things that people hate about flex/bison is actually just their defaults for compatibility with lex/yacc, which can be changed. I have a demo project that does some of the things: https://github.com/o11c/parser-demo