Granular wrapping of the R api

[CGMossa]

It has been a long-term goal of mine, to include the totality of the R C-API in libR-sys. Right now, libR-sys only serves as a sys-crate for extendr, and it primarily follows the needs of extendr.

But it would be nice if libR-sys could be used for all R-API needs in Rust.

To that end, I've made a prototype of how such a project can look like, see https://github.com/CGMossa/modern_libr (see discord discussion for reference) https://discord.com/channels/751419551132155925/751419551132155928/1136068899507540078

Essentially, the resulting lib.rs will roughly look like this

Details

```rs #![allow(non_snake_case)] #![allow(non_upper_case_globals)] #![allow(non_camel_case_types)] #![allow(ambiguous_glob_reexports)] pub mod bindings { #[path = "R.rs"] pub mod r; #[path = "Rinternals.rs"] pub mod r_internals { use super::r_ext::boolean::Rboolean; use super::r_ext::complex::Rcomplex; use super::r_ext::r_dynload::DL_FUNC; include!("bindings/Rinternals.rs"); } #[path = "Rmath.rs"] pub mod r_math; #[path = "Rversion.rs"] pub mod r_version; //TODO: unix specific? // #[path = "Rinterface.rs"] // pub mod r_interface; // pub use r_interface::*; pub mod r_embedded { use super::r_ext::boolean::Rboolean; include!("bindings/Rembedded.rs"); } #[path = "R_ext"] pub mod r_ext { pub mod applic { use super::boolean::Rboolean; include!("bindings/R_ext/Applic.rs"); } pub mod blas { use super::complex::Rcomplex; include!("bindings/R_ext/BLAS.rs"); } // #[path = "Callbacks.rs"] pub mod callbacks { use super::super::r_internals::SEXP; use super::boolean::Rboolean; include!("bindings/R_ext/Callbacks.rs"); } //TODO: another platform? // #[path = "GetX11Image.rs"] // pub mod GetX11Image; // #[path ="Lapack.rs"] pub mod lapack { use super::complex::Rcomplex; include!("bindings/R_ext/Lapack.rs"); } #[path = "Linpack.rs"] pub mod linpack; #[path = "Parse.rs"] pub mod parse { use super::super::r_internals::SEXP; include!("bindings/R_ext/Parse.rs"); } pub mod r_startup { use super::boolean::Rboolean; include!("bindings/R_ext/RStartup.rs"); } pub mod r_dynload { use super::boolean::Rboolean; include!("bindings/R_ext/Rdynload.rs"); } #[path = "Riconv.rs"] pub mod r_iconv; #[path = "Visibility.rs"] pub mod visibility; // TODO: another platform? // #[path ="eventloop.rs"] // pub mod event_loop; #[path = "Boolean.rs"] pub mod boolean; #[path = "Complex.rs"] pub mod complex; #[path = "Arith.rs"] pub mod arith; #[path = "Constants.rs"] pub mod constants; #[path = "Error.rs"] pub mod error; #[path = "Memory.rs"] pub mod memory; #[path = "Print.rs"] pub mod print; #[path = "RS.rs"] pub mod rs; #[path = "Random.rs"] pub mod random; #[path = "Utils.rs"] pub mod utils { use super::complex::Rcomplex; use super::boolean::Rboolean; include!("bindings/R_ext/Utils.rs"); } //TODO: this is windows specific. #[path = "libextern.rs"] pub mod libextern; } #[path = "Rconfig.rs"] pub mod r_config; pub mod r_prelude { pub use super::r_config::*; pub use super::r_ext::arith::*; pub use super::r_ext::boolean::*; pub use super::r_ext::complex::*; pub use super::r_ext::constants::*; pub use super::r_ext::error::*; pub use super::r_ext::libextern::*; pub use super::r_ext::memory::*; pub use super::r_ext::print::*; pub use super::r_ext::random::*; pub use super::r_ext::rs::*; pub use super::r_ext::utils::*; } } ```

There are challenges that need to be dealt with before this can be a reality:

• [x] Faster processing of bindings, as right now, in modern_libr uses clang to filter out elements. Luckily, we are about to land #238 that serves as a schematic for how to accomplish this.
• [ ] Paths to module-files has to be target, R version and platform dependent. This means that the module notation of #[path = <path>] has to depend on these things, for the seamless experience, that is.

[CGMossa]

This effort is continued in #242. While it looks like we are close to this goal, this might not be merged right away.