Text.ParserCombinators.Poly.Result

polyparse-1.12: A variety of alternative parser combinator libraries.

Safe Haskell | Safe
Language | Haskell98

Text.ParserCombinators.Poly.Result

Contents

- The parsing result type

Synopsis

- data Result z a
  - = Success z a
  - | Failure z String
  - | Committed (Result z a)
- resultToEither :: Result z a -> (Either String a, z)

# The parsing result type

data Result z a #

A return type like Either, that distinguishes not only between right and wrong answers, but also has commitment, so that a failure cannot be undone. This should only be used for writing very primitive parsers - really it is an internal detail of the library. The z type is the remaining unconsumed input.

Constructors

Success z a |
Failure z String |
Committed (Result z a) |

Instances

Functor (Result z) # |
Methods fmap :: (a -> b) -> Result z a -> Result z b # (<$) :: a -> Result z b -> Result z a #

resultToEither :: Result z a -> (Either String a, z) #

Convert a Result to an Either, paired with the remaining unconsumed input.