feat: enable match to handle direct recursion

We need to indirect implicitly casted pointers to structs back to their
values in order for match to work similarly for recursive types as it
does for non-recursive types.

Author: scolsen

src/Emit.hs

@@ -384,17 +384,29 @@ toC toCMode (Binder meta root) = emitterSrc (execState (visit startingIndent roo
               emitCaseMatcher :: (String, String) -> String -> XObj -> Integer -> State EmitterState ()
               emitCaseMatcher (periodOrArrow, ampersandOrNot) caseName (XObj (Sym path _) _ t) index =
                 let Just tt = t
-                 in appendToSrc
-                      ( addIndent indent' ++ tyToCLambdaFix tt ++ " " ++ pathToC path ++ " = "
-                          ++ ampersandOrNot
-                          ++ tempVarToAvoidClash
-                          ++ periodOrArrow
-                          ++ "u."
-                          ++ mangle caseName
-                          ++ ".member"
-                          ++ show index
-                          ++ ";\n"
-                      )
+                 in if tt == exprTy
+                      then appendToSrc
+                              ( addIndent indent' ++ tyToCLambdaFix tt ++ " " ++ pathToC path ++ " = "
+                                  ++ "*"
+                                  ++ tempVarToAvoidClash
+                                  ++ periodOrArrow
+                                  ++ "u."
+                                  ++ mangle caseName
+                                  ++ ".member"
+                                  ++ show index
+                                  ++ ";\n"
+                              )
+                      else appendToSrc
+                              ( addIndent indent' ++ tyToCLambdaFix tt ++ " " ++ pathToC path ++ " = "
+                                  ++ ampersandOrNot
+                                  ++ tempVarToAvoidClash
+                                  ++ periodOrArrow
+                                  ++ "u."
+                                  ++ mangle caseName
+                                  ++ ".member"
+                                  ++ show index
+                                  ++ ";\n"
+                              )
               emitCaseMatcher periodOrArrow caseName (XObj (Lst (XObj (Sym (SymPath _ innerCaseName) _) _ _ : xs)) _ _) index =
                 zipWithM_ (\x i -> emitCaseMatcher periodOrArrow (caseName ++ ".member" ++ show i ++ ".u." ++ removeSuffix innerCaseName) x index) xs ([0 ..] :: [Int])
               emitCaseMatcher _ _ xobj _ =