basic enum example

Seeing as we now no longer need to modify generated header files.

lib/GarnetRs/Raw.hs

@@ -29,7 +29,15 @@ import HsBindgen.TH
 import Language.Haskell.TH
 import System.Process
 
+import Control.Monad.IO.Class (MonadIO (liftIO))
+import Language.Haskell.TH.Syntax (addDependentFile)
+import System.Directory.Extra (getCurrentDirectory)
+
 do
+    -- not sure this does anything - hs-bindgen should already be doing the tracking, and the issues are from elsewhere
+    -- dir <- liftIO getCurrentDirectory
+    -- liftIO $ print dir
+    -- addDependentFile $ dir <> "/rust/target/debug/garnet_rs.h"
     systemDirs <- -- TODO bit of a hack
         map (Dir . T.unpack . T.strip)
             . concatMap (takeWhile (maybe False ((== ' ') . fst) . T.uncons) . dropWhile T.null . T.lines)

project.nix

@@ -19,6 +19,8 @@
   };
   overrides = [
     ({ pkgs, ... }: {
+      # TODO get this upstreamed:
+      # https://input-output-hk.github.io/haskell.nix/tutorials/pkg-map.html#mapping-in-haskellnix
       packages.libclang-bindings.components.library = {
         build-tools = [ pkgs.llvmPackages.llvm ];
         libs = [ pkgs.llvmPackages.libclang ];

rust/build.rs

@@ -14,7 +14,6 @@ fn main() {
     // void print_optional(const int8_t *x);
     // and that's only an issue because in HLS TH dependent-file watching gives up after an error
     // i.e. once the containing splice has thrown an exception once, the containing file needs a manual edit to kick it
-    // and that's really not helped by Rust Analyzer mostly only showing diagnostics on save
     // P.S. strings to stdout?! what a terrible API
     // don't get me started in the discoverability of actually then using the terminal for debugging:
     // println!("cargo::warning={:?}", env::var("OUT_DIR"));

rust/lib.rs

@@ -11,7 +11,7 @@ fn say_hello(name: &str) {
 }
 
 #[unsafe(no_mangle)]
-extern "C" fn hello(c: *const c_char) -> () {
+extern "C" fn hello(c: *const c_char) {
     say_hello(unsafe { CStr::from_ptr(c) }.to_str().unwrap())
 }
 
@@ -23,7 +23,7 @@ struct T {
 }
 
 #[unsafe(no_mangle)]
-extern "C" fn hello_struct(t: &T) -> () {
+extern "C" fn hello_struct(t: &T) {
     say_hello(&format!("{:?}", t))
 }
 
@@ -48,7 +48,7 @@ enum Shape {
 }
 
 #[unsafe(no_mangle)]
-extern "C" fn hello_shape(s: &Shape) -> () {
+extern "C" fn hello_shape(s: &Shape) {
     say_hello(&format!("{:?}", s))
 }
 
@@ -93,7 +93,7 @@ enum BTreeC {
 
 #[unsafe(no_mangle)]
 extern "C" fn sum_tree(t: &BTreeC) -> i64 {
-    (unsafe { std::mem::transmute::<_, &BTree<i64>>(t) }).sum()
+    (unsafe { std::mem::transmute::<&BTreeC, &BTree<i64>>(t) }).sum()
 }
 
 #[unsafe(no_mangle)]
@@ -102,9 +102,8 @@ extern "C" fn sum_slice(v: *const i64, s: usize) -> i64 {
 }
 
 #[unsafe(no_mangle)]
-extern "C" fn print_optional(x: Option<&i8>) -> () {
+extern "C" fn print_optional(x: Option<&i8>) {
-    match x {
+    if let Some(x) = x {
-        Some(x) => println!("{}", x / 2),
+        println!("{}", x / 2)
-        None => {}
     }
 }