X-Git-Url: https://git.martlubbers.net/?a=blobdiff_plain;f=src%2Fyard.icl;h=582ea1d6a25e5a8eb2980456c3166622e22263de;hb=2c3c54fbde3f89ed2b87cbf6d4be5d4e7811d694;hp=bded7fb94b2c110c8230f7acf8692c8b91a07de2;hpb=40d54a0715006e2baab1704eef15eecc4076668b;p=cc1516.git diff --git a/src/yard.icl b/src/yard.icl index bded7fb..582ea1d 100644 --- a/src/yard.icl +++ b/src/yard.icl @@ -12,6 +12,7 @@ import Data.Either import Control.Monad import Control.Applicative from Data.Func import $ +import Data.Void instance toString Error where toString ParseError = "General parse error" @@ -24,7 +25,7 @@ runParser (Parser f) i = f i instance + Error where (+) ParseError r = r (+) r ParseError = r - (+) _ r = r + (+) r _ = r instance Functor (Parser a) where fmap f m = liftM f m @@ -60,11 +61,24 @@ top = Parser \i -> case i of [] = (Left ParseError, []) [x:xs] = (Right x, xs) +peek :: Parser a a +peek = Parser \i -> case i of + [] = (Left ParseError, []) + [x:xs] = (Right x, [x:xs]) + +eof :: Parser a Void +eof = Parser \i -> case i of + [] = (Right Void, []) + _ = (Left ParseError, i) + satisfy :: (a -> Bool) -> Parser a a satisfy f = top >>= \r -> if (f r) (return r) fail +check :: (a -> Bool) -> Parser a a +check f = peek >>= \r -> if (f r) (return r) fail + item :: a -> Parser a a | Eq a item a = satisfy ((==)a) list :: [a] -> Parser a [a] | Eq a -list as = mapM item as +list as = mapM item as \ No newline at end of file