Functional Lenses in JavaScript

on YouTube ↗32m

" summary

Builds a tiny lenses library in plain JavaScript: implements a one-line curry function, helpers like prop and assoc, a lens constructor and the operations view/set/over, plus compose/pipe for lens composition. Demonstrates immutable updates on nested JSON (indexing into arrays and changing deep names) and shows the library works with examples, recommends Ramda and monocle-ts for production use, and cautions the demo code is educational rather than production hardened.

AI-written summary · about

" chapters (10)

1. 0:00Introduction
2. 3:16What are lenses
3. 6:51Currying in JavaScript and its benefits
4. 8:13Basic lens implementation
5. 13:33Testing lenses
6. 18:37Lenses for nested objects
7. 22:18Composing lenses
8. 27:18Lens libraries
9. 29:45Functional programming libraries in JavaScript
10. 30:28Fantasy Land overview

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