displaydoc

displaydoc is a Rust derive macro that generates Display implementations from doc comments. Instead of writing #[error("...")] attributes, you write a doc comment on each variant and displaydoc uses it as the display template. It is no_std compatible (implements core::fmt::Display).

Commonly used as a helper alongside thiserror or other error-handling crates when you prefer doc-comment-driven display strings. A pure formatting utility with no runtime overhead. See rust-error-crate-comparison.