From 1fb6cf8e62108fed5984bc363994921ef76280bf Mon Sep 17 00:00:00 2001
From: UberPyro <uberpyro181@gmail.com>
Date: Wed, 27 Sep 2023 06:05:09 +0000
Subject: [PATCH] Run programs with mlton successfully

---
 gibbon-compiler/src/Gibbon/Compiler.hs  | 6 +++++-
 gibbon-compiler/src/Gibbon/L1/GenSML.hs | 4 +++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/gibbon-compiler/src/Gibbon/Compiler.hs b/gibbon-compiler/src/Gibbon/Compiler.hs
index f2cdf0e37..522b36c60 100644
--- a/gibbon-compiler/src/Gibbon/Compiler.hs
+++ b/gibbon-compiler/src/Gibbon/Compiler.hs
@@ -585,10 +585,14 @@ compileMPL fp = do
 
 runMPL :: FilePath -> IO ()
 runMPL fp = do
-  cd <- system $ "./" <> dropExtension fp
+  cd <- system $ prefix <> dropExtension fp
   case cd of
     ExitFailure n -> error $ "SML executable failed with code " <> show n
     ExitSuccess -> pure ()
+  where
+    prefix = case takeDirectory fp of
+      "" -> "./"
+      _ -> ""
 
 goSML :: Config -> L1.Prog1 -> (FilePath -> IO a2) -> StateT b IO L1.Prog1
 goSML config prog acts = 
diff --git a/gibbon-compiler/src/Gibbon/L1/GenSML.hs b/gibbon-compiler/src/Gibbon/L1/GenSML.hs
index 393137f68..516e9a368 100644
--- a/gibbon-compiler/src/Gibbon/L1/GenSML.hs
+++ b/gibbon-compiler/src/Gibbon/L1/GenSML.hs
@@ -317,7 +317,9 @@ reduceFunDefs keyword funDef doc =
 ppMainExpr :: Maybe (Exp1, b) -> Doc
 ppMainExpr opt = case opt of
   Nothing -> mempty
-  Just (exp0, _) -> "val _ = " <> ppE exp0 <> semi
+  Just (exp0, _) -> 
+    "val _ = " <> ppE exp0 <> semi
+    <> "\nval _ = print \"\\n\""
 
 ppDDefs :: DDefs1 -> Doc
 ppDDefs ddefs = case elems ddefs of