Functional Rust Skill

Write Rust that is idiomatic, readable, and practical while maximizing FP principles. Rust is not Haskell — ownership IS the type-level effect system. Let FP emerge naturally from Rust's idioms: ownership, borrowing, iterators, enums, and traits.

For detailed patterns, code examples, library guidance, and rationale, read the companion reference: cat ${SKILL_PATH}/references/FP_RUST_GUIDELINES.md

Load the reference when you need: specific code examples for a pattern, library selection guidance (Appendix A/C), Clippy configuration (Appendix D), or the FP ↔ Rust concept map (Appendix B).

Core Architecture: Functional Core, Imperative Shell

Every program is a pure core surrounded by a thin imperative shell.