Optics Journeys
Four journeys covering the full optics surface, from first-principles Lens and Prism up to the Focus DSL. Work them in order: each builds on concepts introduced earlier.
The .focus().attributes().at(key) token in One Line, Six Layers is the optic layer; these journeys teach the pieces that compose into that one fluent path. The reference material lives in the Optics chapter.
| Journey | Focus | Duration | Exercises |
|---|---|---|---|
| Lens & Prism | Lens basics, composition, Prism, Affine | ~40 min | 30 |
| Traversals & Practice | Traversals, composition, real-world applications | ~40 min | 27 |
| Fluent & Free DSL | Fluent API, advanced Prism patterns, Free Monad DSL | ~35 min | 22 |
| Focus DSL | Type-safe path navigation, container widening | ~35 min | 29 |
Next: Lens & Prism