Allow parsing signed integers

really-bad-compiler-in-haskell.cabal

@@ -18,7 +18,6 @@ executable really-bad-compiler-in-haskell
   other-modules:
       Forth.LLVMGen
       Forth.Parser
-      Forth.Types.Expr
       Forth.Types.Token
       Paths_really_bad_compiler_in_haskell
   hs-source-dirs:

src/Forth/LLVMGen.hs

@@ -7,7 +7,7 @@
 module Forth.LLVMGen (llvmGen) where
 
 import Data.ByteString (ByteString)
-import Forth.Types.Expr as Expr
+import Forth.Types.Token as Token
 import LLVM (moduleLLVMAssembly, withModuleFromAST)
 import LLVM.AST hiding (function)
 import LLVM.AST.Type
@@ -17,7 +17,7 @@ import LLVM.IRBuilder.Instruction
 import LLVM.IRBuilder.Module
 import LLVM.IRBuilder.Monad
 
-getLLVM :: Expr -> Module
+getLLVM :: Token -> Module
 getLLVM expr =
   buildModule "program" $ mdo
     -- TODO: better module name
@@ -32,22 +32,22 @@ exprToLLVM ::
   ( MonadIRBuilder m,
     MonadModuleBuilder m
   ) =>
-  Expr ->
+  Token ->
   m Operand
 exprToLLVM (Lit prim) = pure $ primToLLVM prim
-exprToLLVM (Expr.Add a b) = mdo
+exprToLLVM (Token.Add a b) = mdo
   lhs <- exprToLLVM a
   rhs <- exprToLLVM b
   add lhs rhs
-exprToLLVM (Expr.Sub a b) = mdo
+exprToLLVM (Token.Sub a b) = mdo
   lhs <- exprToLLVM a
   rhs <- exprToLLVM b
   sub lhs rhs
-exprToLLVM (Expr.Mul a b) = mdo
+exprToLLVM (Token.Mul a b) = mdo
   lhs <- exprToLLVM a
   rhs <- exprToLLVM b
   mul lhs rhs
-exprToLLVM (Expr.Div a b) = mdo
+exprToLLVM (Token.Div a b) = mdo
   lhs <- exprToLLVM a
   rhs <- exprToLLVM b
   sdiv lhs rhs
@@ -55,7 +55,7 @@ exprToLLVM (Expr.Div a b) = mdo
 primToLLVM :: Int -> Operand
 primToLLVM i = int32 (fromIntegral i)
 
-llvmGen :: Expr -> IO ByteString
+llvmGen :: Token -> IO ByteString
 llvmGen expr = do
   let l = getLLVM expr
   withContext

src/Forth/Parser.hs

@@ -19,16 +19,18 @@ lexeme :: Parser a -> Parser a
 lexeme = L.lexeme C.space
 
 int :: Parser Int
-int = lexeme L.decimal
+int = lexeme $ L.signed (return ()) L.decimal
 
 symbol :: Text -> Parser Text
 symbol = L.symbol C.space
 
 item :: Parser Token
 item =
-  Lit
-    <$> int
-      <|> Add
+  try
+    ( Lit
+        <$> int
+    )
+    <|> Add
     <$ symbol "+"
       <|> Sub
     <$ symbol "-"

src/Main.hs

@@ -3,13 +3,10 @@
 
 module Main (main) where
 
--- import Compiler.ExeGen
-
 import Data.ByteString.Char8 qualified as B
 import Data.Text.IO qualified as T
 import Forth.LLVMGen
 import Forth.Parser
-import Forth.Types.Expr
 import System.Environment
 import System.Process