external_doc - The Rust Unstable Book

# `external_doc`

The tracking issue for this feature is: #44732

The `external_doc` feature allows the use of the `include` parameter to the `#[doc]` attribute, to include external files in documentation. Use the attribute in place of, or in addition to, regular doc comments and `#[doc]` attributes, and `rustdoc` will load the given file when it renders documentation for your crate.

With the following files in the same directory:

`external-doc.md`:

    # My Awesome Type

    This is the documentation for this spectacular type.

`lib.rs`:

    #![feature(external_doc)]

    #[doc(include = "external-doc.md")]
    pub struct MyAwesomeType;

`rustdoc` will load the file `external-doc.md` and use it as the documentation for the `MyAwesomeType` struct.

When locating files, `rustdoc` will base paths in the `src/` directory, as if they were alongside the `lib.rs` for your crate. So if you want a `docs/` folder to live alongside the `src/` directory, start your paths with `../docs/` for `rustdoc` to properly find the file.

This feature was proposed in RFC #1990 and initially implemented in PR #44781.