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fix: pr comments

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Gabriel Cruz 2026-07-10 16:24:22 -03:00
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README.md
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@ -136,15 +136,18 @@ you need a name that differs from the proc.
### ABI format
The default wire format is `cbor`. Override the library default with
`declareLibrary("lib", Lib, defaultABIFormat = "c")`, or per annotation with an
`"abi = ..."` spec, e.g. `{.ffi: "abi = c".}`.
The wire format is chosen **in code**, never by a compile flag. Override the
library default with `declareLibrary("lib", Lib, defaultABIFormat = "c")`, or
per annotation with an `"abi = ..."` spec, e.g. `{.ffi: "abi = c".}`. The
`-d:targetLang` flag (below) picks which *language* the bindings are emitted
for; it does not change the wire.
`cbor` is the fully-supported format: every proc, ctor, dtor and event
serializes through the generic CBOR path, and all four binding backends emit
`cbor` is the default and fully-supported format: every proc, ctor, dtor and
event serializes through the generic CBOR path, and all binding generators emit
working callers for it.
`abi = c` (flat C-struct wire, generated by `-d:targetLang=c_abi`) is newer and
`abi = c` is a newer, flat C-struct wire (no CBOR round-trip). Callers for it
are emitted only by the dedicated `c_abi` generator (`-d:targetLang=c_abi`). It
carries two honest limits today:
- **Events are CBOR-only.** Applying `abi = c` to an `{.ffiEvent.}` proc is a
@ -153,10 +156,10 @@ carries two honest limits today:
- **All-scalar `abi = c` procs are dropped from the foreign bindings.** A
`{.ffi: "abi = c".}` method whose every param and return is a plain scalar
takes the CBOR-free scalar fast path at runtime, but the foreign codegen for
that inline-args shape is a follow-up — such procs are omitted from the
generated `.h`. Give a proc at least one non-scalar (struct / `seq` /
`Option`) param or return, or use `abi = cbor`, if you need it in the
bindings.
that inline-args shape is a follow-up (tracked in #120) — such procs are
omitted from the generated `.h`. Give a proc at least one non-scalar
(struct / `seq` / `Option`) param or return, or use `abi = cbor`, if you need
it in the bindings.
## Placement of `genBindings()`
@ -184,7 +187,9 @@ nim c --app:lib --noMain --nimMainPrefix:libmylib mylib.nim
**2. Emit the foreign bindings** — same flags, plus the binding defines. This
compile runs the generators as a compile-time side effect and produces no
runnable output, so send the binary to `/dev/null`:
runnable output, so send the binary to `/dev/null`. The generated files (for
`targetLang=c`/`c_abi`: the `<name>.h` header your host includes, plus a
`CMakeLists.txt`) land in `-d:ffiOutputDir`:
```sh
nim c --app:lib --noMain --nimMainPrefix:libmylib \
@ -193,7 +198,11 @@ nim c --app:lib --noMain --nimMainPrefix:libmylib \
-o:/dev/null mylib.nim
```
- `-d:targetLang` — `rust` (default), `cpp`, `c`, `c_abi`, or `cddl`.
- `-d:targetLang` — which generator runs. Two kinds:
- **Language bindings over the CBOR wire:** `rust` (default), `cpp`, `c`.
- **Non-peer generators:** `c_abi` — C bindings that speak the flat `abi = c`
wire instead of CBOR; `cddl` — a CDDL schema of the CBOR wire, not a
language binding at all.
- `-d:ffiOutputDir` — where the generated files land.
- `-d:ffiSrcPath` — the Nim source path embedded in the generated build files.