Document feature flags using crate document-features (#1725)

emath/Cargo.toml

@@ -22,14 +22,23 @@ all-features = true
 [features]
 default = []
 
-# Enable additional checks if debug assertions are enabled (debug builds).
+## Enable additional checks if debug assertions are enabled (debug builds).
 extra_debug_asserts = []
-# Always enable additional checks.
+## Always enable additional checks.
 extra_asserts = []
 
 
 [dependencies]
-# Optional:
+#! ### Optional dependencies
+
+## [`bytemuck`](https://docs.rs/bytemuck) enables you to cast `emath` types to `&[u8]`.
 bytemuck = { version = "1.7.2", optional = true, features = ["derive"] }
+
+## [`mint`](https://docs.rs/mint) enables interopability with other math libraries such as [`glam`](https://docs.rs/glam) and [`nalgebra`](https://docs.rs/nalgebra).
 mint = { version = "0.5.6", optional = true }
+
+## Allow serialization using [`serde`](https://docs.rs/serde).
 serde = { version = "1", optional = true, features = ["derive"] }
+
+# Needed when generating the docs, but unfortunately also needed by `cargo check`
+document-features = "0.2"

emath/src/lib.rs

@@ -14,6 +14,10 @@
 //!
 //! For that, use something else ([`glam`](https://docs.rs/glam), [`nalgebra`](https://docs.rs/nalgebra), …)
 //! and enable the `mint` feature flag in `emath` to enable implicit conversion to/from `emath`.
+//!
+//! ## Feature flags
+#![doc = document_features::document_features!()]
+//!
 
 #![allow(clippy::float_cmp)]
 #![allow(clippy::manual_range_contains)]