Awesome
doc-gen4
Document Generator for Lean 4
Usage
doc-gen4
is easiest to use via its custom Lake facet. The currently recommended setup for
this is that you create a nested project for documentation building inside of your lake project.
To do this:
- Create a subdirectory within your existing lake project called
docbuild
- Create a
lakefile.toml
withindocbuild
with the following content:
name = "docbuild"
reservoir = false
version = "0.1.0"
packagesDir = "../.lake/packages"
[[require]]
name = "Your Library Name"
path = "../"
[[require]]
scope = "leanprover"
name = "doc-gen4"
# Use revision v4.x if you are developing against a stable Lean version.
rev = "main"
- Run
lake update doc-gen4
withindocbuild
to pindoc-gen4
and its dependencies to the chosen versions. - If your parent project has dependencies you want to run
lake update YourLibraryName
withindocbuild
whenever you update the dependencies of your parent project.
After this setup step you can generate documentation for an entire library and all files imported
by that library using the following command within docbuild
:
lake build YourLibraryName:docs
If you have multiple libraries you want to generate full documentation for:
lake build Test:docs YourLibraryName:docs
Note that doc-gen4
currently always generates documentation for Lean
, Init
, Lake
and Std
in addition to the provided targets.
The root of the built docs will be docbuild/.lake/build/doc/index.html
.
However, due to the "Same Origin Policy", the generated website will be partially broken if you just
open the generated html files in your browser. You need to serve them from a proper http server for
it to work. An easy way to do that is to run python3 -m http.server
from the docbuild/.lake/build/doc
directory.
Requirements to run doc-gen4
In order to compile itself doc-gen4
requires:
- a Lean 4 or
elan
installation - a C compiler if on Linux or MacOS (on Windows it will use Lean's built-in clang compiler)
Apart from this the only requirement for lake build YourLibraryName:docs
to work is that your
target library builds, that is lake build YourLibraryName
exits without an error. If this requirement
is not fulfilled, the documentation generation will fail and you will end up with
partial build artefacts in docbuild/.lake/build/doc
. Note that doc-gen4
is perfectly capable of
generating documentation for Lean code that contains sorry
, just not for code
that doesn't compile.
If you are working on a project that only partially compiles but can't fix the
errors from the top of your head, you can try to remove import
s of both the failing files
and all files that refer to the failing ones from your top level library file.
Like this you will end up with an incomplete documentation but at least working
documentation of your project.
Note that we do not recommend this approach and suggest to instead make sure your
projects always compile by using CI to prevent broken code from being added and sorry
-ing
out things that you intend to complete later.
Source locations
Source locations default to guessing the Github repo for the library, but different different schemas can be used by setting the DOCGEN_SRC
environment variable. For
example, one can use links that open the local source file in VSCode by running lake with:
DOCGEN_SRC="vscode" lake ...
The different options are:
DOCGEN_SRC="github"
infers the Github project for each library and uses source links to the Github source view. This is the default ifDOCGEN_SRC
is unset.DOCGEN_SRC="file"
creates references to local file references.DOCGEN_SRC="vscode"
creates VSCode URLs to local files.
How does docs#Nat.add
from the Lean Zulip work?
If someone sends a message that contains docs#Nat.add
on the Lean Zulip this will
automatically link to Nat.add
from the mathlib4
documentation. The way that this
feature is implemented is by linking to /find
of generated documentation in the following way:
https://example.com/path/to/docs/find/?pattern=Nat.add#doc in the case of the mathlib4
documentation this ends up being to: https://leanprover-community.github.io/mathlib4_docs/find/?pattern=Nat.add#doc.
If you wish to provide a similar feature to docs#Nat.add
from the Lean Zulip for your documentation,
this is the way to go.
Development of doc-gen4
You can build docs using a modified doc-gen4
as follows: Replace the doc-gen4
require from
docbuild with:
[[require]]
name = "doc-gen4"
path = "../../path/to/your/doc-gen4"
Note that if you modify the .js
or .css
files in doc-gen4
, they won't necessarily be copied over when
you rebuild the documentation. You can manually copy the changes to the docbuild/.lake/build/doc
directory to make
sure the changes appear, or just do a full recompilation (lake clean
and lake build
inside the doc-gen4
directory.)