How can I write lenses without depending on lens?

Part of the magic of lens (referring to the package) is that you can write lenses (referring to the concept) without actually depending on lens. This page provides a guide for package maintainers who'd like to add lens-compatible lenses to their library incurring minimal dependencies. It covers all of the basic lens types: Lens, Prism, Iso, Traversal, Fold, Getter, Setter, Review, Action, and Mona

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"Part of the magic of lens (referring to the package) is that you can write lenses (referring to the concept) without actually depending on lens."