Playing with Shapeless

on YouTube ↗23m

" summary

Play-Formless generates Play Framework Form mappings from case classes using Shapeless (LabelledGeneric, HLists and singleton-typed symbols) so a full form can be derived in one line of code. It provides type-driven defaults via polymorphic function values, handles refined types to turn type-level constraints into runtime validators, and enables type-safe field access with symbol names checked at compile time. It works at compile time with negligible runtime overhead but has rough IDE support and sometimes obscure compile errors.

AI-written summary · about

" chapters (9)

1. 0:00Introduction to talk
2. 1:06Play Framework form mappings
3. 3:11Problems with current approach
4. 4:59How Shapeless integration works
5. 8:09Transforming HLists to mappings
6. 13:12Default mappings from types
7. 16:46Refined types integration
8. 19:26Benefits and downsides
9. 20:50About Interval and Q&A

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