dwmckee/cpp2lox

A casual attempt to reproduce Robert Nystrom's lox in Herb Sutter's C++ syntax 2

cpp2lox

A casual attempt to reproduce Robert Nystrom's lox in Herb Sutter's C++ syntax 2 (that is targeting cppfront as the compiler).

Build

The current build is based on meson and requires at least version 0.55.0 (for support of the patch_directory feature in wrap files).

Build credit

I shamelessly stole the meson build support for cppfront from Jussi Pakkanen's cpp2meson repository, only I took advantage of patch_directory to maintain the build file in my repository instead of creating a cutout for cppfront. Thanks, Jussi!

Discussion

There are plenty of things that cppfront does not yet support, and that is going to affect how we write the code.

By design there is no support for owning raw pointers and unsafe allocation strategies like new. This means I have to decide between using mixed code to implement the garbage collector or simply using a cpp2 arena in the first place. The latter is more convenient but the former more in keeping with the pedagogical nature of Crafting Interpreters. I've already given up on explicit dynamic arrays in favor of std::vector but that is largely because I've long been conversant with dynamic arrays in C, so they don't offer me anything new.

The cppfront separate compilation scheme is not well explained in the docs. It seems to be a unity build, but either way, I got it working for now. In the long run cppfront is based on C++20 and beyond, so it will use modules. Alas module support is uneven and fragile on most tools chains right now and the build tool I adopted (meson) has no support at all right now.

Repository

I intend to tag version for places where the book and I both get to a working intermediate state.