Make alex{G,S}etUserState available with monadUserState-bytestring wrapper (#254)

Corrects some CPP in the template.

Closes #220.

---------

Co-authored-by: Emeka Nkurumeh <[email protected]>

Author: andreasabel

CHANGELOG.md

@@ -3,6 +3,8 @@
  * Add option `--numeric-version`.
  * Remove deprecated `-v` as alias for `--version`.
  * Add `-v` as placeholder for a future `--verbose` option.
+ * Make `alex{G,S}etUserState` available with the `monadUserState-bytestring` wrapper
+   [Issue #220](https://github.com/haskell/alex/issues/220).
 
 ## Changes in 3.4.0.1
 

data/AlexWrappers.hs

@@ -360,13 +360,13 @@ alexGetStartCode = Alex $ \s@AlexState{alex_scd=sc} -> Right (s, sc)
 alexSetStartCode :: Int -> Alex ()
 alexSetStartCode sc = Alex $ \s -> Right (s{alex_scd=sc}, ())
 
-#if !defined(ALEX_MONAD_BYTESTRING) && defined(ALEX_MONAD_USER_STATE)
+#if defined(ALEX_MONAD_USER_STATE)
 alexGetUserState :: Alex AlexUserState
 alexGetUserState = Alex $ \s@AlexState{alex_ust=ust} -> Right (s,ust)
 
 alexSetUserState :: AlexUserState -> Alex ()
 alexSetUserState ss = Alex $ \s -> Right (s{alex_ust=ss}, ())
-#endif /* !defined(ALEX_MONAD_BYTESTRING) && defined(ALEX_MONAD_USER_STATE) */
+#endif /* defined(ALEX_MONAD_USER_STATE) */
 
 #ifdef ALEX_MONAD
 alexMonadScan = do

tests/monadUserState_typeclass_bytestring.x

@@ -70,6 +70,11 @@ lex inp =
   let
     lexAll =
       do
+        -- Andreas Abel, 2023-12-30, issue #220:
+        -- Test that alex{G,S}etUserState are in scope.
+        u <- alexGetUserState
+        alexSetUserState (u + 1)
+
         res <- alexMonadScan
         case res of
           EOF -> return []

tests/tokens_monadUserState_bytestring.x

@@ -28,30 +28,39 @@ tokens :-
 tok f (p,_,input,_) len = return (f p (B.take (fromIntegral len) input))
 
 -- The token type:
-data Token =
-	Let AlexPosn		|
-	In  AlexPosn		|
-	Sym AlexPosn Char	|
-        Var AlexPosn String     |
-	Int AlexPosn Int	|
-        Err AlexPosn            |
-        EOF
-        deriving (Eq,Show)
+data Token
+  = Let AlexPosn
+  | In  AlexPosn
+  | Sym AlexPosn Char
+  | Var AlexPosn String
+  | Int AlexPosn Int
+  | Err AlexPosn
+  | EOF
+  deriving (Eq,Show)
 
 alexEOF = return EOF
 
 main = if test1 /= result1 then do print test1; exitFailure
-			   else exitWith ExitSuccess
+                           else exitWith ExitSuccess
 
 type AlexUserState = ()
 alexInitUserState = ()
 
 scanner str = runAlex str $ do
-  let loop = do tk <- alexMonadScan
-                if tk == EOF
-                        then return [tk]
-			else do toks <- loop
-                                return (tk:toks)
+  let
+    loop = do
+
+      -- Andreas Abel, 2023-12-30, issue #220:
+      -- Test that alex{G,S}etUserState are in scope.
+      () <- alexGetUserState
+      alexSetUserState ()
+
+      tk <- alexMonadScan
+      if tk == EOF
+          then return [tk]
+          else do
+            toks <- loop
+            return (tk:toks)
   loop
 
 test1 = case scanner "  let in 012334\n=+*foo bar__'" of