Rust API Design: Using Docs, Semantic Types, and Zero-Sized Types for Clarity

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A technical guide on DEV Community outlines advanced Rust API design principles focused on making interfaces intuitive and difficult to misuse. It recommends writing thorough documentation that covers edge cases such as panics, errors, and unsafe function conditions. Developers are advised to include end-to-end crate-level examples so users can understand how components work together, rather than relying solely on isolated method-level docs. The guide also suggests organizing documentation with modules, internal links, and the #[doc(hidden)] attribute to hide legacy interfaces without removing them. Additional principles covered include the use of semantic types and zero-sized types to encode constraints directly into the type system.

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