🖨️ Half a printing function (does not work)

a3/a3-handout/src/APL/Parser.hs

@@ -49,6 +49,10 @@ lVName = lexeme $ try $ do
     then fail "Unexpected keyword"
     else pure v
 
+lStringLit :: Parser String
+lStringLit =
+  lexeme $ read <$> some (satisfy isAlpha) <* notFollowedBy (satisfy isAlphaNum)
+
 lInteger :: Parser Integer
 lInteger =
   lexeme $ read <$> some (satisfy isDigit) <* notFollowedBy (satisfy isAlphaNum)
@@ -66,6 +70,10 @@ lBool =
       const False <$> lKeyword "false"
     ]
 
+pStringLit :: Parser String
+pStringLit =
+  lString "\"" *> lStringLit <* lString "\""
+
 pAtom :: Parser Exp
 pAtom =
   choice
@@ -93,6 +101,9 @@ pLExp =
         <$> (lKeyword "if" *> pExp)
         <*> (lKeyword "then" *> pExp)
         <*> (lKeyword "else" *> pExp),
+      Print
+        <$> (lKeyword "print" *> pStringLit)
+        <*> pExp,
       pFExp
     ]
 
@@ -101,8 +112,7 @@ pPExp = pLExp >>= chain
   where
     chain x =
       choice
-        [
-          do
+        [ do
             lString "**"
             y <- pPExp
             chain $ Pow x y,

a3/a3-handout/src/APL/Parser_Tests.hs

@@ -82,5 +82,9 @@ tests =
         [ parserTest "x ** y" $ Pow (Var "x") (Var "y"),
           parserTest "x ** y ** z" $ Pow (Var "x") (Pow (Var "y") (Var "z")),
           parserTest "x + y ** z * x" $  Add (Var "x") (Mul (Pow (Var "y") (Var "z")) (Var "x"))
+        ],
+      testGroup
+        "Print"
+        [ parserTest "print \"test\" y" $ Print "test" (Var "y")
         ]
     ]