:: Ord a => [a] -> [a] -package:html-entities -package:Cabal-syntax -package:imports -package:integration -package:safe -package:mono-traversable -package:amazonka-core -package:Cabal -package:statistics -package:witherable -package:ghc -package:basement package:parsers
Take a parser that may consume input, and on failure, go back to where
we started and fail as if we didn't consume input.