extendr-api v0.8.1 fails to compile: SEXPTYPE::OBJSXP not found (E0599)

[IoannaThoma]

extendr-api v0.8.1 fails to compile due to missing SEXPTYPE::OBJSXP.
Reproduction steps:

• cargo build
• cargo tree -p extendr-api

Cargo output:
error[E0599]: no variant or associated item named OBJSXP found for enum extendr_ffi::SEXPTYPE in the current scope
--> .cargo/registry/src/index.crates.io-1949cf8c6b5b557f/extendr-api-0.8.1/src/lib.rs:564:32
|
564 | Rtype::S4 => SEXPTYPE::OBJSXP,
| ^^^^^^ variant or associated item not found in SEXPTYPE

error[E0599]: no variant or associated item named OBJSXP found for enum extendr_ffi::SEXPTYPE in the current scope
--> .cargo/registry/src/index.crates.io-1949cf8c6b5b557f/extendr-api-0.8.1/src/lib.rs:598:19
|
598 | SEXPTYPE::OBJSXP => Rtype::S4,
| ^^^^^^ variant or associated item not found in SEXPTYPE
Notes:

• cargo build exits with "could not compile extendr-api (lib) due to 2 previous errors".
• I believe crates.io publish of extendr-api v0.8.1 expects an older extendr-ffi that exposes OBJSXP - the extendr-ffi version cargo resolved appears not to expose that variant.

My understanding is that extendr-api from crates.io fails to compile against the extendr-ffi that cargo resolves.
Or extendr-api's crate on crates.io is broken because it depends on an older internal API that no longer exists.

Cargo tree (relevant portion)
codelist v0.1.0 (repos/codelist-tools/bindings/r/src/rust)
├── codelist-rs v0.1.0 (https://github.com/ehrtools/codelist-tools.git#410377a0)
│ ├── ...
├── extendr-api v0.8.1
│ ├── extendr-ffi v0.8.1
│ ├── extendr-macros v0.8.1 (proc-macro)
│ ├── once_cell v1.21.3
│ └── paste v1.0.15 (proc-macro)
└── extendr-ffi v0.8.1

codelist-rs v0.1.0 (repos/codelist-tools/rust/codelist-rs)
├── ...
├── extendr-api v0.8.1 (*)
├── extendr-ffi v0.8.1
├── ...

codelist-validator-rs v0.1.0 (/repos/codelist-tools/rust/codelist-validator-rs)
├── ...
├── extendr-api v0.8.1 (*)
├── extendr-ffi v0.8.1
├── ...

(Note: cargo tree shows extendr-api v0.8.1 and extendr-ffi v0.8.1 are the versions being used.)

rustc --version
rustc 1.88.0 (6b00bc388 2025-06-23)
cargo --version
cargo 1.88.0 (873a06493 2025-05-10)

uname -srvmp && cat /etc/os-release 2>/dev/null || sw_vers 2>/dev/null

Darwin 24.6.0 Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:40 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6041 arm64 arm
ProductName: macOS
ProductVersion: 15.6
BuildVersion: 24G84

[IoannaThoma]

@CarolineMorton, I hope this helps.