For example, in this tokio-rs doc , there is the This is supported on crate feature rt only. How do we add that do the docs? I can't find it anywhere; tokio's source code does not seem to have that explicitly.

I'm a Tokio maintainer. Here are the steps to do this: First you add this to your Cargo.toml: [package.metadata.docs.rs] all-features = true rustdoc-args = ["--cfg", "docsrs"] This will make docs.rs compile your documentation with RUSTFLAGS="--cfg docsrs" set. We can use this to conditionally ena…

Awesome, thanks a lot. I had to change it to RUSTDOCFLAGS="--cfg docsrs" to the local run. Tokio is using the same on the CI . So, RUSTDOCFLAGS="--cfg docsrs" cargo +nightly doc --features full seems sufficient here (RUSTFLAGS is not needed apparently).

Ah I mixed them up, yes. The RUSTFLAGS variable is for setting stuff in dependencies of the crate being documented. I edited the previous post.

How to document optional features in API docs

help

jhpratt September 9, 2021, 6:24am 2

It's an unstable attribute. Tracking issue. In the future it's hoped that the docs will get it right automatically, with the attribute only existing for a manual override.

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How to document optional features in API docs

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