variable and function context between prompts

1 files changed, 24 insertions, 7 deletions

diff --git a/src/main.hs b/src/main.hs
index 34a190a..569ba28 100644
--- a/src/main.hs
+++ b/src/main.hs
@@ -2,17 +2,26 @@ import System.IO
 import Statement
 import Parser.Statement
 import Parser.Core
+import Statement
+import Assignment
+import Expr
+import Evaluation
+
 
+main = promptLoop []
 
-main = do
+promptLoop :: Context -> IO ()
+promptLoop context = do
     line <- prompt
-    loop line
+    if line /= "exit"
+       then loop line context >>= promptLoop
+       else return ()
 
-loop :: String -> IO ()
-loop "exit" = return ()
-loop line   = do s <- parseIO line
-                 putStrLn $ show s
-                 main
+loop :: String -> Context -> IO Context
+loop line context = do s <- parseIO line
+                       context <- printStatement s context
+                       putStrLn $ show context
+                       return context
 
 prompt :: IO String
 prompt = do putStr "> "
@@ -23,3 +32,11 @@ parseIO :: String -> IO Statement
 parseIO input = case parseStrict statementP input of
                   Nothing -> fail "Couldn't parse input"
                   Just s  -> return s
+
+printStatement :: Statement -> Context -> IO Context
+printStatement (SAssignment a) context = do putStrLn $ show a
+                                            return $ update context a
+printStatement (SExpr e) context = do putStrLn evalStr
+                                      return context
+    where evalStr = case eval context e of Nothing -> "Couldn't evaluate expression"
+                                           Just a  -> show a