:: Ord a => [a] -> [a] -package:html-entities -package:base -package:Cabal-syntax -package:containers -package:vector-algorithms -package:ghc -package:witherable is:exact -package:lens -package:mono-traversable -package:Cabal -package:hedgehog 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.