Generalize op2 type parameter. (#64)

* Generalize `op2` type parameter.

* Add CI

* cabal install hspec-discover

* hspec-discover

* `cabal test`

Author: dmjio

.github/workflows/ci.yml

@@ -0,0 +1,38 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  build:
+    runs-on: macos-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install ArrayFire
+        run: brew install arrayfire
+
+      - name: Set up GHC
+        uses: haskell-actions/setup@v2
+        with:
+          ghc-version: '9.8.4'
+          cabal-version: 'latest'
+
+      - name: Cache cabal store
+        uses: actions/cache@v4
+        with:
+          path: ~/.cabal/store
+          key: ${{ runner.os }}-cabal-${{ hashFiles('cabal.project', '*.cabal') }}
+          restore-keys: |
+            ${{ runner.os }}-cabal-
+
+      - name: Configure
+        run: cabal configure --flags="disable-default-paths disable-build-tool-depends" --extra-include-dirs=$(brew --prefix arrayfire)/include --extra-lib-dirs=$(brew --prefix arrayfire)/lib
+
+      - name: Build
+        run: cabal build arrayfire
+

src/ArrayFire/FFI.hs

@@ -72,7 +72,7 @@ op2
   :: Array b
   -> Array a
   -> (Ptr AFArray -> AFArray -> AFArray -> IO AFErr)
-  -> Array a
+  -> Array c
 {-# NOINLINE op2 #-}
 op2 (Array fptr1) (Array fptr2) op =
   unsafePerformIO $ do

test/Main.hs

@@ -20,6 +20,7 @@ instance (A.AFType a, Arbitrary a) => Arbitrary (Array a) where
 
 main :: IO ()
 main = do
+  A.setBackend A.CPU
 --  checks (Proxy :: Proxy (A.Array (A.Complex Float)))
 --  checks (Proxy :: Proxy (A.Array (A.Complex Double)))
 --  checks (Proxy :: Proxy (A.Array Double))