How to Totally Fix PartialFunction

on YouTube ↗49m

" summary

Argument: PartialFunction breaks expectations by inheriting from Function1 and redefining apply, which weakens Liskov substitution and causes surprising runtime MatchErrors. Concrete proposals: split semantics with an explicit unsafeApply and safe apply/orElse, or remove the inheritance so Function1 and PartialFunction are distinct, or implement PartialFunction on an unboxed Option/opaque type to avoid boxing. Notes: small compatibility fixes already merged for 2.13, full migration costs and compiler/typechecks are the main obstacles.

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" chapters (10)

1. 0:00Introduction
2. 2:54Agenda
3. 3:44Definitions
4. 8:33PartialFunction
5. 15:07Partial Function When
6. 17:51Implementation
7. 25:56Partial Functions
8. 27:20Proposal
9. 31:36Proposed Solution
10. 37:22Alternative Solution

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