comline-rust

The Rust target for Comline — one repo per language, holding that language's codegen, libgen, runtime and std-extra together.

Today: just codegen/ (comline-codegen-rust), extracted from ComlineProject/generation. The FFI / dylib (lib-mode) work is gated pending a rewrite against the current IR (G2c); a runtime and std-extra follow.

codegen/

comline-codegen-rust — frozen IR → Rust source.

• code — one <namespace>.rs per schema: serde data types, plain traits, C-like enums.
• lib — a buildable crate: Cargo.toml + src/lib.rs (module tree) + src/<namespace>.rs.

Depends on comline-codegen (the language-neutral contract + Registry) and comline-core (the IR), both by git rev. register(&mut Registry) contributes the generator under rust from version 1.85.0 on (its floor: generated code can't build on older Rust); the Comline CLI composes it into its Registry at startup.

cargo test

The rust_c_ffi/, rust_abi_stable/, lib_gen_rust*/ modules are kept for reference but not built — they target a pre-audit FrozenUnit and need a rewrite, not a port.

Features

What this generator implements, feature by feature. Each claim is checked by the conformance suite in ComlineProject/generation: a supported feature has a fixture that generates and matches its golden output, an ignored one generates exactly what it would without the feature, and an unsupported one is refused with an error naming every use. The full matrix, with the fixtures that prove each claim, is in FEATURES.md.

Feature	rust ≥ 1.85.0
structs structs	✅ supported
enums enums	✅ supported
optional fields optional-fields	✅ supported
arrays arrays	✅ supported
fixed-length arrays fixed-arrays	✅ supported
fixed arrays over 32 elements, nested large-fixed-arrays-nested	❌ unsupported: a fixed array over 32 elements renders only as a struct or error field's own, non-optional type (serde's derive stops at 32)
unions unions	❌ unsupported: Rust has no anonymous sum type to render one as
type aliases type-aliases	✅ supported
constants constants	✅ supported
protocols protocols	✅ supported
errors errors	✅ supported
functions that throw throws	✅ supported
validators validators	✅ supported
imports between schemas imports	✅ supported
nested namespaces nested-namespaces	✅ supported
lib mode lib-mode	✅ supported
external_std external-std	✅ supported
validate_on_decode validate-on-decode	✅ supported
JSON-RPC framing framing-jsonrpc	✅ supported
no handshake handshake-none	✅ supported
connections connections	✅ supported
async async	✅ supported
the packed@1 format format-packed	✅ supported
the json@1 format format-json	✅ supported
the msgpack@1 format format-msgpack	✅ supported
bounds bounds	✅ supported
single characters chars	✅ supported

Design

See ComlineProject/docs → Design:

• Runtime & generation repository structure — why one repo per language
• Generation — what codegen / libgen / runtime each mean
• The core ↔ target contract — the boundary this repo builds against

License

GNU General Public License v3.0 only (LICENSE or https://www.gnu.org/licenses/gpl-3.0.html). This generator links comline-core and is part of Comline's GPL toolchain. Copyleft covers the generator, not the code it emits — generated bindings are yours and link only comline-runtime (MPL-2.0). Contributions are GPL-3.0-only. Rationale + per-repo split: design/licensing.md.