When working on a book/guide for a repository you'll sometimes find yourself wanting to import some of your source code into your guide so that you can discuss it or provide higher level context.

mdbook comes with a way to #include in between two line numbers in a file - but this can be prone to link rot when you modify a file but forget to modify all of the sections in your guide that refer to a file.

Bookimport seeks to address this by allowing you to import sections of a file by annotating the file.

This allows you to modify the code between the annotations as much as you like and the import will still behave as you originally intended.

Bookimport was originally created to close mdbook issue #879.

cargo install mdbook-bookimport

{{#bookimport ../book.toml@book-section }}

Annotate any file with.

# #![allow(unused_variables)]
#fn main() {
// @book start some-tag
// ... contents go here ...
// @book end some-tag
#}

Bookimport only looks for the @book {start,end} some-tag, so depending on the file type that you're in you'll want to comment thoe annotation out appropriately.

Here's how to use bookimport to import a section of a file labeled book-section.

<!-- Without the / symbol -->

/{{#bookimport  ../book.toml@book-section }}

# Contents of book.toml

# ...

# @book start book-section
src = "src"
title = "The Mdbook Bookimport Book"
# @book end book-section

# ...