1 files changed, 48 insertions, 5 deletions
diff --git a/lib/Language/Elna/Frontend/AST.hs b/lib/Language/Elna/Frontend/AST.hs
index 0925f6f..037e6ca 100644
--- a/lib/Language/Elna/Frontend/AST.hs
+++ b/lib/Language/Elna/Frontend/AST.hs
@@ -15,9 +15,10 @@ module Language.Elna.Frontend.AST
 import Data.Char (chr)
 import Data.Int (Int32)
 import Data.List (intercalate)
-import Data.Word (Word8, Word32)
+import Data.Word (Word8)
 import Language.Elna.Location (Identifier(..), showArrayType)
 import Numeric (showHex)
+import Data.Bifunctor (Bifunctor(bimap))
 
 newtype Program = Program [Declaration]
     deriving Eq
@@ -57,13 +58,14 @@ showParameters parameters =
 
 data TypeExpression
     = NamedType Identifier
-    | ArrayType Word32 TypeExpression
+    | ArrayType Literal TypeExpression
     deriving Eq
 
 instance Show TypeExpression
   where
     show (NamedType typeName) = show typeName
-    show (ArrayType elementCount typeName) = showArrayType elementCount typeName
+    show (ArrayType elementCount typeName) =
+        showArrayType elementCount typeName
 
 data Statement
     = EmptyStatement
@@ -96,18 +98,59 @@ data VariableDeclaration =
     deriving Eq
 
 data Literal
-    = IntegerLiteral Int32
+    = DecimalLiteral Int32
     | HexadecimalLiteral Int32
     | CharacterLiteral Word8
     deriving Eq
 
 instance Show Literal
   where
-    show (IntegerLiteral integer) = show integer
+    show (DecimalLiteral integer) = show integer
     show (HexadecimalLiteral integer) = '0' : 'x' : showHex integer ""
     show (CharacterLiteral character) =
         '\'' : chr (fromEnum character) : ['\'']
 
+instance Ord Literal
+  where
+    compare x y = compare (int32Literal x) (int32Literal y)
+
+instance Num Literal
+  where
+    x + y = DecimalLiteral $ int32Literal x + int32Literal y
+    x * y = DecimalLiteral $ int32Literal x * int32Literal y
+    abs (DecimalLiteral x) = DecimalLiteral $ abs x
+    abs (HexadecimalLiteral x) = HexadecimalLiteral $ abs x
+    abs (CharacterLiteral x) = CharacterLiteral $ abs x
+    negate (DecimalLiteral x) = DecimalLiteral $ negate x
+    negate (HexadecimalLiteral x) = HexadecimalLiteral $ negate x
+    negate (CharacterLiteral x) = CharacterLiteral $ negate x
+    signum (DecimalLiteral x) = DecimalLiteral $ signum x
+    signum (HexadecimalLiteral x) = HexadecimalLiteral $ signum x
+    signum (CharacterLiteral x) = CharacterLiteral $ signum x
+    fromInteger = DecimalLiteral . fromInteger
+
+instance Real Literal
+  where
+    toRational (DecimalLiteral integer) = toRational integer
+    toRational (HexadecimalLiteral integer) = toRational integer
+    toRational (CharacterLiteral integer) = toRational integer
+
+instance Enum Literal
+  where
+   toEnum = DecimalLiteral . fromIntegral
+   fromEnum = fromEnum . int32Literal
+
+instance Integral Literal
+  where
+    toInteger = toInteger . int32Literal
+    quotRem x y = bimap DecimalLiteral DecimalLiteral
+        $ quotRem (int32Literal x) (int32Literal y)
+
+int32Literal :: Literal -> Int32
+int32Literal (DecimalLiteral integer) = integer
+int32Literal (HexadecimalLiteral integer) = integer
+int32Literal (CharacterLiteral integer) = fromIntegral integer
+
 instance Show VariableDeclaration
   where
     show (VariableDeclaration identifier typeExpression) =