Sometimes, you may want to build up a computation using Reader env value where
the value is a result that may or may not fail. Elm already provides us with the
Result err value that provides this functionality.
However, working with nested ADT can be cumbersome. This module exposes the type
Except env err val which is just a type alias for a Reader env (Result err val)
and provides some useful functions for mapping over or chaining such nested computations.
Embed a successful value inside a Reader.
Embeds a failure inside a Reader.
Apply a function to the resulting value of the Reader if successful.
Apply a function embeded in an Except to a successful value in an Except.
Chain Excepts together.
Discards one level of Except
The Except type wraps the result from a Reader into a Result.