Data.Digit.D1

Documentation

class D1 d where

Minimal complete definition

d1

Methods

d1 :: Prism' d ()

x1 :: d

Instances

D1 ()

Methods

d1 :: Prism' () ()

x1 :: ()

D1 Digit

Methods

d1 :: Prism' Digit ()

x1 :: Digit

parse1 :: (D1 d, CharParsing p) => p d

>>> parse (parse1 <* eof) "test" "1" :: Either ParseError Digit
Right 1

>>> parse parse1 "test" "1xyz" :: Either ParseError Digit
Right 1

>>> isn't _Right (parse parse1 "test" "xyz" :: Either ParseError Digit)
True

\c -> c /= '1' ==> isn't _Right (parse parse1 "test" [c] :: Either ParseError Digit)