Reference, "src/doc/reference", "reference", submodule;
RustByExample, "src/doc/rust-by-example", "rust-by-example", submodule;
RustdocBook, "src/doc/rustdoc", "rustdoc";
+ StyleGuide, "src/doc/style-guide", "style-guide";
);
fn open(builder: &Builder<'_>, path: impl AsRef<Path>) {