fix for subtraction - final code cleanup

felixbd · Nov 27, 2023 · 4d14639 · 4d14639
1 parent 8518b8e
commit 4d14639
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diff --git a/README.org b/README.org
@@ -10,61 +10,65 @@ Parser and interpreter for the While programming language
 *** example
 
 #+begin_src shell
-felix in ~/git-repos/hub/while on main λ stack run
+felix in ~/git-repos/hub/while on main ● λ stack build
+felix in ~/git-repos/hub/while on main ● λ stack run
 
  = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
 
+Enter the file name:
+./examples/simple.while
 [READING .WHILE FILE] "./examples/simple.while"
-[MetaToken {getLineNumber = 1, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 1, getToken = AssignToken},
- MetaToken {getLineNumber = 1, getToken = ConstToken {getConstInt = 10}},
- MetaToken {getLineNumber = 1, getToken = SemicolonToken},
- MetaToken {getLineNumber = 2, getToken = VarToken {getVarName = "x_2"}},
- MetaToken {getLineNumber = 2, getToken = AssignToken},
- MetaToken {getLineNumber = 2, getToken = ConstToken {getConstInt = 0}},
- MetaToken {getLineNumber = 2, getToken = SemicolonToken},
- MetaToken {getLineNumber = 4, getToken = WhileToken},
- MetaToken {getLineNumber = 4, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 4, getToken = NotEqualToken},
- MetaToken {getLineNumber = 4, getToken = ConstToken {getConstInt = 0}},
- MetaToken {getLineNumber = 4, getToken = DoToken},
- MetaToken {getLineNumber = 5, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 5, getToken = AssignToken},
- MetaToken {getLineNumber = 5, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 5, getToken = MinusToken},
- MetaToken {getLineNumber = 5, getToken = ConstToken {getConstInt = 1}},
- MetaToken {getLineNumber = 5, getToken = SemicolonToken},
- MetaToken {getLineNumber = 6, getToken = LoopToken},
- MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 6, getToken = DoToken},
- MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_2"}},
- MetaToken {getLineNumber = 6, getToken = AssignToken},
- MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_2"}},
- MetaToken {getLineNumber = 6, getToken = PlusToken},
- MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_1"}},
- MetaToken {getLineNumber = 6, getToken = EndToken},
- MetaToken {getLineNumber = 7, getToken = EndToken}]
-
- = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
 
+[DONE TOKENIZE]:
+[MetaToken {getLineNumber = 1, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 1, getToken = AssignToken},
+MetaToken {getLineNumber = 1, getToken = ConstToken {getConstInt = 10}},
+MetaToken {getLineNumber = 1, getToken = SemicolonToken},
+MetaToken {getLineNumber = 2, getToken = VarToken {getVarName = "x_2"}},
+MetaToken {getLineNumber = 2, getToken = AssignToken},
+MetaToken {getLineNumber = 2, getToken = ConstToken {getConstInt = 0}},
+MetaToken {getLineNumber = 2, getToken = SemicolonToken},
+MetaToken {getLineNumber = 4, getToken = WhileToken},
+MetaToken {getLineNumber = 4, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 4, getToken = NotEqualToken},
+MetaToken {getLineNumber = 4, getToken = ConstToken {getConstInt = 0}},
+MetaToken {getLineNumber = 4, getToken = DoToken},
+MetaToken {getLineNumber = 5, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 5, getToken = AssignToken},
+MetaToken {getLineNumber = 5, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 5, getToken = MinusToken},
+MetaToken {getLineNumber = 5, getToken = ConstToken {getConstInt = 1}},
+MetaToken {getLineNumber = 5, getToken = SemicolonToken},
+MetaToken {getLineNumber = 6, getToken = LoopToken},
+MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 6, getToken = DoToken},
+MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_2"}},
+MetaToken {getLineNumber = 6, getToken = AssignToken},
+MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_2"}},
+MetaToken {getLineNumber = 6, getToken = PlusToken},
+MetaToken {getLineNumber = 6, getToken = VarToken {getVarName = "x_1"}},
+MetaToken {getLineNumber = 6, getToken = EndToken},
+MetaToken {getLineNumber = 7, getToken = EndToken}]
+
+[DONE PARSING AST]:
 Sequential
 	(Assignment "x_1" (Constant {getConst = 10}))
 	(Sequential
 		(Assignment "x_2" (Constant {getConst = 0}))
 		(While
 			(Neq (Variable {getVar = "x_1"}) (Constant {getConst = 0}))
-				(Sequential
-					(Assignment "x_1" (Subtract (Variable {getVar = "x_1"}) (Constant {getConst = 1})))
-					(Loop
-						(Variable {getVar = "x_1"})
-						(Assignment "x_2" (Add (Variable {getVar = "x_2"}) (Variable {getVar = "x_1"})))))))
+			(Sequential
+				(Assignment "x_1" (Subtract (Variable {getVar = "x_1"}) (Constant {getConst = 1})))
+				(Loop
+					(Variable {getVar = "x_1"})
+					(Assignment "x_2" (Add (Variable {getVar = "x_2"}) (Variable {getVar = "x_1"})))))))
 
- = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
-
-[OUTPUT]:
+[OUTPUT OF EVALUATION]:
 [("x_2",285),("x_1",0)]
 
  = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
+
+felix in ~/git-repos/hub/while on main ● λ
 #+end_src
 
 *** compile

diff --git a/app/Main.hs b/app/Main.hs
@@ -3,29 +3,30 @@
 
 module Main (main) where
 
-import WhileParser (WhileAST(..), tokenize, readFileContent, runASTParser)
-import WhileEvaluation (eval, evalM, VarName, VarVal, VarState, VarStateWorld)
+import WhileParser (tokenize, readFileContent, runASTParser)  -- WhileAST(..),
+import WhileEvaluation (eval) --, evalM, VarName, VarVal, VarState, VarStateWorld)
 
 
 main :: IO ()
 main = do
-
   putStrLn $ "\n" ++ concat (replicate 40 " =") ++ "\n"
 
-  whileLines <- readFileContent "./examples/simple.while"
+  -- Prompt the user for the file name
+  putStrLn "Enter the file name:"
+  fileName <- getLine
+
+  -- Read the content of the specified file
+  whileLines <- readFileContent fileName  -- "./examples/simple.while"
   let tokens = tokenize whileLines
 
+  putStrLn "\n\ESC[92m[DONE TOKENIZE]\ESC[0m:"
   print tokens
 
-  putStrLn $ "\n" ++ concat (replicate 40 " =") ++ "\n"
-
   let astOfFoo = runASTParser tokens
+  putStrLn "\n\ESC[92m[DONE PARSING AST]\ESC[0m:"
   print astOfFoo
 
-  putStrLn $ "\n" ++ concat (replicate 40 " =") ++ "\n"
-
-  putStrLn "\ESC[92m[OUTPUT]\ESC[0m:"
-
+  putStrLn "\n\ESC[92m[OUTPUT OF EVALUATION]\ESC[0m:"
   let a = eval astOfFoo []
   print a
 

diff --git a/src/WhileEvaluation.hs b/src/WhileEvaluation.hs
@@ -61,25 +61,24 @@ updateVarState name val states | name `notElem` map fst states = (name, val):sta
 --------------------------------------------------------------------------------
 
 evalExpression :: Expression -> VarStateWorld -> Int
-evalExpression exp state = case exp of
+evalExpression expr state = case expr of
                              (Constant c)         -> c
                              (Variable varName)   -> lookUpVarState varName state
                              (Add exp1 exp2)      -> helper (+) [exp1, exp2]
-                             (Subtract exp1 exp2) -> evalExpression exp1 state - evalExpression exp2 state
+                             (Subtract exp1 exp2) -> max 0 $ evalExpression exp1 state - evalExpression exp2 state
                              (Neq exp1 exp2)      -> fromEnum $ evalExpression exp1 state /= evalExpression exp2 state
-                             _                    -> undefined
   where
     -- helper :: (Int -> Int -> Int) -> [Expression] -> Int
     helper f = foldl (\acc x -> f acc (evalExpression x state)) 0
 
 --------------------------------------------------------------------------------
 
 evalAssignment :: WhileAST -> VarStateWorld -> VarStateWorld
-evalAssignment (Assignment name exp) state = updateVarState name (evalExpression exp state) state
+evalAssignment (Assignment name expr) state = updateVarState name (evalExpression expr state) state
 evalAssignment _ _ = undefined
 
 evalWhileExp :: WhileAST -> VarStateWorld -> VarStateWorld
-evalWhileExp (While exp whileAST) state = helperWhile exp whileAST state
+evalWhileExp (While expr whileAST) state = helperWhile expr whileAST state
 evalWhileExp _ _ = undefined
 
 -- NOTE maybe check if `evalExpression p state` returns either 0 or 1 ...
@@ -90,7 +89,7 @@ helperWhile p ast state = if evalExpression p state == 1
 
 evalLoopExp :: WhileAST -> VarStateWorld -> VarStateWorld
 -- evalLoopExp (Loop exp whileAST) state = (foldr (.) id (replicate (evalExpression exp state) eval))
-evalLoopExp (Loop exp whileAST) state = helperLoop whileAST state (evalExpression exp state)
+evalLoopExp (Loop expr whileAST) state = helperLoop whileAST state (evalExpression expr state)
 evalLoopExp _ _ = undefined
 
 helperLoop :: WhileAST -> VarStateWorld -> Int -> VarStateWorld
@@ -107,7 +106,6 @@ eval ast vs = case ast of
                 w@(While _ _)           -> evalWhileExp w vs
                 l@(Loop _ _)            -> evalLoopExp l vs
                 Pass                    -> vs
-                _                       -> vs
 
 evalT :: WhileAST -> VarStateT ()
 evalT ast w = ((), eval ast w)

diff --git a/src/WhileParser.hs b/src/WhileParser.hs
@@ -2,6 +2,7 @@
 -- | (c) 2023 Felix Drees - BSD3 License
 
 {-# LANGUAGE LambdaCase #-}
+{-# OPTIONS_GHC -Wno-partial-fields #-}
 
 module WhileParser
   (Token(..)