From 62528a6d75df48ea9717967133161ce612b9fc50 Mon Sep 17 00:00:00 2001
From: Laborratte5 <laborratte5@gmail.com>
Date: Thu, 18 Jul 2024 18:04:36 +0200
Subject: [PATCH] Implement AbstractSyntaxTree

---
 app/AbstractSyntaxTree.hs        | 36 ++++++++++++++++++++++++++++++++
 app/Main.hs                      |  5 ++++-
 simple-arithmetic-compiler.cabal |  2 +-
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 app/AbstractSyntaxTree.hs

diff --git a/app/AbstractSyntaxTree.hs b/app/AbstractSyntaxTree.hs
new file mode 100644
index 0000000..009ccdc
--- /dev/null
+++ b/app/AbstractSyntaxTree.hs
@@ -0,0 +1,36 @@
+module AbstractSyntaxTree where
+
+import qualified Parser
+
+type AST = Node
+
+data Node = Operation Opcode Node Node
+          | Scalar Int
+          deriving Show
+
+data Opcode = Add
+            | Sub
+            | Mult
+            | Div
+            deriving Show
+
+createAST :: Parser.CST -> AST
+createAST = simplifyExpr
+
+simplifyExpr :: Parser.Expr -> Node
+simplifyExpr expr = case expr of
+    Parser.Add term expr2 -> Operation Add (simplifyTerm term) (simplifyExpr expr2)
+    Parser.Sub term expr2 -> Operation Sub (simplifyTerm term) (simplifyExpr expr2)
+    Parser.ETerm term -> simplifyTerm term
+
+simplifyTerm :: Parser.Term -> Node
+simplifyTerm term = case term of
+    Parser.Mult factor term2 -> Operation Mult (simplifyFactor factor) (simplifyTerm term2)
+    Parser.Div  factor term2 -> Operation Div  (simplifyFactor factor) (simplifyTerm term2)
+    Parser.TFactor factor -> simplifyFactor factor
+
+simplifyFactor :: Parser.Factor -> Node
+simplifyFactor factor = case factor of
+    Parser.Integer i -> Scalar i
+    Parser.Parantheses expr -> simplifyExpr expr
+    Parser.NegFactor  factor2 -> Operation Mult (Scalar (-1)) (simplifyFactor factor2)
diff --git a/app/Main.hs b/app/Main.hs
index 4eeddb7..7d519fa 100644
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -2,8 +2,11 @@ module Main where
 
 import qualified Lexer
 import qualified Parser
+import qualified AbstractSyntaxTree as AST
 
 main :: IO ()
 main = do
   source <- readFile "arithmetic.txt"
-  putStr $ show (Parser.parse $ Lexer.lex source)
+  case Parser.parse $ Lexer.lex source of
+    Just source -> print $ AST.createAST source
+    _ -> putStr "Some error"
diff --git a/simple-arithmetic-compiler.cabal b/simple-arithmetic-compiler.cabal
index 629dee5..7f36a32 100644
--- a/simple-arithmetic-compiler.cabal
+++ b/simple-arithmetic-compiler.cabal
@@ -52,7 +52,7 @@ executable simple-arithmetic-compiler
     main-is:          Main.hs
 
     -- Modules included in this executable, other than Main.
-    other-modules:    Lexer, Parser
+    other-modules:    Lexer, Parser, AbstractSyntaxTree
 
     -- LANGUAGE extensions used by modules in this package.
     -- other-extensions: