delete guileslop and add haskellslop

examples/hs/plain-ghc/Hello.hs

@@ -0,0 +1,15 @@
+module Main where
+
+import Foreign (Int32)
+
+
+foreign export ccall "hello" hello :: IO Int32
+
+hello :: IO Int32
+hello = do
+  putStrLn "hello from Haskell!!!"
+  pure 0
+
+main :: IO ()
+main = error "defining main shouldn't be necessary since we set -no-hs-main, \
+             \but HLS is yelling at me and i just want to calm her down."

examples/hs/plain-ghc/Hello_stub.h

@@ -0,0 +1,9 @@
+#include <HsFFI.h>
+#if defined(__cplusplus)
+extern "C" {
+#endif
+extern HsInt32 hello(void);
+#if defined(__cplusplus)
+}
+#endif
+

examples/hs/plain-ghc/Shakefile.hs

@@ -0,0 +1,39 @@
+import Development.Shake
+import Development.Shake.Command
+import Development.Shake.FilePath
+import Development.Shake.Util
+import Data.Char (toUpper)
+
+capitalise (x:xs) = toUpper x : xs
+
+ghcflags =
+  [ "-no-hs-main"
+  , "-optl-mexec-model=reactor"
+  , "-optl-Wl,--export=hello,--export=hs_init"
+  ]
+
+main = shakeArgs shakeOptions $ do
+  want ["call-hello.wasm","hello.wasm"]
+  "call-hello.wasm" %> \out -> do
+    need ["call-hello.wat"]
+    cmd_ "wasm-tools parse call-hello.wat" "-o" [out]
+  "hello.wasm" %> \out -> do
+      need ["Hello.hs"]
+      cmd_
+        "wasm32-wasi-ghc"
+        "Hello.hs" ghcflags
+        "-o" [out]
+  phony "run" $ do
+    need ["call-hello.wasm","hello.wasm"]
+    cmd_ "wasmtime run"
+      "--preload" "env=hello.wasm"
+      "--invoke" "call-hello"
+      "call-hello.wasm"
+  phony "clean" $ do
+    removeFilesAfter ".shake" ["//*"]
+    liftIO $ removeFiles "."
+      [ "*.wasm"
+      , "*.o"
+      , "*_stub.h"
+      , "*.hi"
+      ]

examples/hs/plain-ghc/call-hello.wat

@@ -0,0 +1,6 @@
+(module
+ (import "env" "hello" (func $hello (result i32)))
+ (import "env" "hs_init" (func $hs-init (param i32 i32)))
+ (func (export "call-hello") (result i32)
+       (call $hs-init (i32.const 0) (i32.const 0))
+       (call $hello)))