Add some example for new operator `~`

[0xff-dev]

First of all, thank you very much for providing so many examples. Go1.18 released the generic, learned the example of the generic from the website of the repository, and found that there was a lack of introduction to the ~ operator. Should we add an example of the operator ~?

[eliben]

Open to suggestions here. A good, useful example can be added to the Generics page -- make suggestions in a PR