| The enum `Either` with variants `Left` and `Right` is a general purpose | |
| sum type with two cases. | |
| Either has methods that are similar to Option and Result, and it also implements | |
| traits like `Iterator`. | |
| Includes macros `try_left!()` and `try_right!()` to use for | |
| short-circuiting logic, similar to how the `?` operator is used with `Result`. | |
| Note that `Either` is general purpose. For describing success or error, use the | |
| regular `Result`. |