Fix serializer, + compilation.

Eval.hs

+{-# Language ImportQualifiedPost #-}
+
 module Eval where
 
 import Data.Map.Strict qualified as Map

Serialize.hs

 module Serialize where
 
+import Data.Char (ord, chr)
 import Expression
 
-serialize :: Expression -> String
-serialize (Number x) =
-    chr . (+ 33) . fromInteger <$>
-        [(x `div` 94^b) `mod` 94
-        | b <- [digits, digits-1 .. 0]]
-    where digits = floor $ logBase 94 (fromInteger x)
+encodeNumber :: Integer -> String
+encodeNumber x = [chr(fromInteger a + 33) | a <- [mod (div x (94^b)) 94 | b<-[y,y-1..0]]]
+    where y = floor $ logBase 94.0 (fromInteger x)
+
+
+
+serialize (Number x) = 'I':encodeNumber x
+serialize (Str x)          = 'S':fmap (chr . (+ 33) . ord) x
+serialize (Boolean True)   = "T"
+serialize (Boolean False)  = "F"
+serialize (Variable x)     = 'V':(fmap (chr . (+ 33) . ord) $ encodeNumber x)
+serialize (Lambda x y)     = "L"    ++ fmap (chr . (+ 33) . ord) (encodeNumber x) ++ " " ++ serialize y
+serialize (Negate x)       = "U- "  ++ serialize x
+serialize (Not x)          = "U! "  ++ serialize x
+serialize (StringToInt x)  = "U# "  ++ serialize x
+serialize (IntToString  x) = "U$ "  ++ serialize x
+serialize (Add x y)        = "B+ "  ++ serialize x ++ " " ++ serialize y
+serialize (Sub x y)        = "B- "  ++ serialize x ++ " " ++ serialize y
+serialize (Mul x y)        = "B* "  ++ serialize x ++ " " ++ serialize y
+serialize (Div x y)        = "B/ "  ++ serialize x ++ " " ++ serialize y
+serialize (Mod x y)        = "B% "  ++ serialize x ++ " " ++ serialize y
+serialize (Gt x y)         = "B> "  ++ serialize x ++ " " ++ serialize y
+serialize (Lt x y)         = "B< "  ++ serialize x ++ " " ++ serialize y
+serialize (Eq x y)         = "B= "  ++ serialize x ++ " " ++ serialize y
+serialize (Or x y)         = "B| "  ++ serialize x ++ " " ++ serialize y
+serialize (And x y)        = "B& "  ++ serialize x ++ " " ++ serialize y
+serialize (Concat x y)     = "B++ " ++ serialize x ++ " " ++ serialize y
+serialize (Take x y)       = "BT "  ++ serialize x ++ " " ++ serialize y
+serialize (Drop x y)       = "BD "  ++ serialize x ++ " " ++ serialize y
+serialize (Apply x y)      = "B$ "  ++ serialize x ++ " " ++ serialize y
+serialize (If x y z)       = "? "   ++ serialize x ++ " " ++ serialize y ++ " " ++ serialize z
 

main.hs

+{-# Language ImportQualifiedPost #-}
+
 import Data.Map.Strict qualified as Map
 import Text.Parsec (parse)
 import Control.Monad.Reader (runReader)

serialize.hs

-module Serialize where
-
-import Data.Char (ord, chr)
-import Expression
-
-serialize :: Expression -> String
-serialize (Number x) = 'I':[chr((fromInteger a) + 33) | a <- [mod (div x (94^b)) 94 | b<-[y,y-1..0]]]
-    where y = floor ( logBase 94.0 (fromInteger x) )
-serialize (Str x) = 'S':[chr((ord a) + 33)|a<-x]
-serialize (Boolean x) = if x
-                          then "T"
-                          else "F"
-serialize (Variable x) = "V" . [chr(ord(x)+33)]
-serialize (Lambda x y) = "L" . [chr(ord(x)+33)] . " " . (serialize y)
-serialize (Negate x) = "U- " . (serialize x)
-serialize (Not x) = "U! " . (serialize x)
-serialize (StringToInt x) = "U# " . (serialize x)
-serialize (IntToString  x) = "U$ " . (serialize x)
-serialize (Add x y) = "B+ " .  (serialize x) . " " . (serialize y)
-serialize (Sub x y) = "B- " .  (serialize x) . " " . (serialize y)
-serialize (Mul x y) = "B* " . (serialize x) . " " . (serialize y)
-serialize (Div x y) =  "B/ " . (serialize x) . " " . (serialize y)
-serialize (Mod x y) =  "B% " . (serialize x) . " " . (serialize y)
-serialize (Gt x y) =  "B> " . (serialize x) . " " . (serialize y)
-serialize (Lt x y) =  "B< " . (serialize x) . " " . (serialize y)
-serialize (Eq x y) =  "B= " . (serialize x) . " " . (serialize y)
-serialize (Or x y) =  "B| " . (serialize x) . " " . (serialize y)
-serialize (And x y) = "B& " . (serialize x) . " " . (serialize y)
-serialize (Concat x y) = "B. " . (serialize x) . " " . (serialize y)
-serialize (Take x y) = "BT " . (serialize x) . " " . (serialize y)
-serialize (Drop x y) = "BD " . (serialize x) . " " . (serialize y)
-serialize (Apply x y) = "B$ " . (serialize x) . " " . (serialize y)
-serialize (If x y z) = "? " . (serialize x) . " " . (serialize y) . " " . (serialize z)
-