Correctly parse negative numbers

1 files changed, 1 insertions, 1 deletions

diff --git a/Parser.hs b/Parser.hs
index 44e58cb..b331bf0 100644
--- a/Parser.hs
+++ b/Parser.hs
@@ -43,7 +43,7 @@ pVList = flip label "list" $ do
     return $ VList exs
 
 pVNum :: Parser Value
-pVNum = liftM (VNum . read) (many1 digit) <* pWhiteComment  <?> "number"
+pVNum = liftM (VNum . read) (try (char '-' >> many1 digit) <|> many1 digit) <* pWhiteComment  <?> "number"
 
 pVString :: Parser Value
 pVString = fmap VString pString