:: Ord a => [a] -> [a] -package:list-t -package:mono-traversable -package:safe -package:ghc -package:Cabal-syntax -package:amazonka-core -package:Cabal -package:errors -package:lifted-base -package:witherable -package:vector package:parsers -is:exact
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.