Adding Kind-polymorphism To The Scala Programming Language

on YouTube ↗51m

" summary

Argues Scala needs kind-polymorphism so generic derivation can move out of macros into the compiler, enabling shapeless-style features without fragile macro internals. Shows a working typelevel Scala prototype and an experimental Dotty -Y flag implementation that accept type parameters of any kind; poly-kinded type parameters work, but polytype application (applying poly-kinded constructors to arguments) remains unimplemented. Result: prototype compiles and is usable for many cases, it revives interest and points to follow-up work to finish poly-application and land a full poly-kinded generic primitive.

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" chapters (8)

1. 0:00Introduction and background
2. 8:54Macros in Scala ecosystem
3. 16:00Kind polymorphism explained
4. 22:52Generic type classes in Shapeless
5. 32:04Need for kind polymorphism
6. 37:31Proof of concept implementation
7. 46:57Current status and future work
8. 50:17Q&A

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