How to stop fighting with coherence and star writing context-generic trait impls
summary
Proposes Context-Generic Programming (CGP) and a released CGP30 crate that generates provider traits and type-level lookup tables so multiple overlapping, formerly-illegal trait implementations compile as distinct providers; uses macros like CGB component and delegate components macro to wire providers into a concrete context. Demonstrated on a messaging library where switching the context changes serialization (hex vs base64) without touching library code; works today but has steep learning curve and noisy error messages.
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chapters (15)
- 0:00Introduction
- 1:14Rust trait system and coherence
- 5:49Hash table problem and coherence
- 8:59Existing coherence solutions
- 11:47Specialization limitations
- 13:51Remote trait pattern with Serde
- 15:56Provider traits bypass coherence
- 19:47Context and implicit parameters
- 23:44Context-driven programming
- 24:48CGP30 crate and compatibility
- 28:58Demo of modular serialization
- 33:13Hash problem solved with CGP
- 34:39CGP use cases and future
- 35:20CGP challenges and learning
- 37:06Q&A
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