compile-time config

config/config.json

@@ -0,0 +1,4 @@
+{
+    "wasm": true,
+    "rust": true
+}

config/configure.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+# This script should be run from the root of the project
+
+if [ `basename "$PWD"` != "juvix" ] || [ ! -d "config" ]; then
+    echo "This script should be run from the root of the project"
+    exit 1
+fi
+
+if clang -target wasm32-wasi --print-supported-cpus >/dev/null 2>&1; then
+    WASM="true"
+else
+    WASM="false"
+fi
+
+if rustc --version >/dev/null 2>&1; then
+    RUST="true"
+else
+    RUST="false"
+fi
+
+printf "{\n    \"wasm\": $WASM,\n    \"rust\": $RUST\n}\n" > config/config.json

package.yaml

@@ -43,6 +43,8 @@ extra-source-files:
   - runtime/vampir/*.pir
   - runtime/casm/*.casm
   - runtime/nockma/*.nockma
+  - config/config.json
+  - config/configure.sh
 
 dependencies:
   - aeson-better-errors == 0.9.*

src/Juvix/Config.hs

@@ -0,0 +1,28 @@
+module Juvix.Config where
+
+import Data.Aeson
+import Data.ByteString.Lazy qualified as BL
+import Data.FileEmbed qualified as FE
+import Juvix.Prelude
+
+data Config = Config
+  { _configWasm :: Bool,
+    _configRust :: Bool
+  }
+  deriving stock (Show, Eq, Generic)
+
+makeLenses ''Config
+
+instance FromJSON Config where
+  parseJSON = genericParseJSON opts
+    where
+      opts =
+        defaultOptions
+          { fieldLabelModifier = map toLower . dropPrefix "_config"
+          }
+
+config :: Config
+config =
+  fromMaybe (Config False False) $
+    decode $
+      BL.fromStrict $(FE.makeRelativeToProject "config/config.json" >>= FE.embedFile)