The selectors approach is clever, given that it works without a `map_err` closure but still supports borrows through the `Into` conversion. Unfortunately, all t

The selectors approach is clever, given that it works without a `map_err` closure but still supports borrows through the `Into` conversion. Unfortunately, all the libraries before yours have ruined the chances of me using anything outside of libstd as far as error-handling is concerned ( https://news.ycombinator.com/item?id=22820661 https://news.ycombinator.com/item?id=22820661 ).