Use do to parse numbers

This is not necessarily better than the `liftM` method (probably isn't).

diff --git a/app/Main.hs b/app/Main.hs
index 58017c55305aa90095ba786e78ed009df4209040..87b94aa3650c31697794c5e2c6c17706d88219ef 100644 (file)
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -34,7 +34,10 @@ parseAtom = do
                 _    -> Atom atom
 
 parseNumber :: Parser LispVal
-parseNumber = liftM (Number . read) $ many1 digit
+parseNumber = do
+    ds <- many1 digit
+    let a = read ds
+    return $ Number a
 
 parseExpr :: Parser LispVal
 parseExpr = parseString