Use maybe instead of fromMaybe and fmap

src/ShellCheck/Analytics.hs

@@ -5020,7 +5020,7 @@ checkPlusEqualsNumber params t =
         let
             unquotedLiteral = getUnquotedLiteral word
             isEmpty = unquotedLiteral == Just ""
-            isUnquotedNumber = not isEmpty && fromMaybe False (all isDigit <$> unquotedLiteral)
+            isUnquotedNumber = not isEmpty && maybe False (all isDigit) unquotedLiteral
             isNumericalVariableName = fromMaybe False $ do
                 str <- unquotedLiteral
                 CF.variableMayBeAssignedInteger state str

src/ShellCheck/CFGAnalysis.hs

@@ -829,7 +829,7 @@ lookupStack' functionOnly get dep def ctx key = do
     f (s:rest) = do
         -- Go up the stack until we find the value, and add
         -- a dependency on each state (including where it was found)
-        res <- fromMaybe (f rest) (return <$> get (stackState s) key)
+        res <- maybe (f rest) return (get (stackState s) key)
         modifySTRef (dependencies s) $ S.insert $ dep key res
         return res