# doc-gen4
Document Generator for Lean 4

## Usage
`doc-gen4` is the easiest to use via its custom Lake facet, in order
to do this you have to add it to your `lakefile.lean` like this:
```
meta if get_config? env = some "dev" then -- dev is so not everyone has to build it
require «doc-gen4» from git "https://github.com/leanprover/doc-gen4" @ "main"
```

Then update your dependencies:
```
lake -Kenv=dev update
```

Then you can generate documentation for an entire library and all files imported
by that library using:
```
lake -Kenv=dev build Test:docs
```
If you have multiple libraries you want to generate full documentation for:
```
lake -Kenv=dev build Test:docs Foo:docs
```
Note that doc-gen currently always generates documentation for `Lean`, `Init`
and `Lake` in addition to the provided targets.

## Development of doc-gen4
You can build docs using a modified `doc-gen4` as follows:  Replace the `from git  "..." @ "main"` in the `lakefile.lean` with just `from "..."` using the path to the modified version of `doc-gen4`.  E.g. if the
path to the modified version of `doc-gen4` is `../doc-gen4`, it would be:
```
meta if get_config? env = some "dev" then -- dev is so not everyone has to build it
require «doc-gen4» from "../doc-gen4"
```

The root of the built docs will be `build/docs/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 `build/docs` directory.

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 `build/docs` directory to make
sure the changes appear, or just do a full recompilation (`lake clean` and `lake build` inside the `doc-gen4`
directory.)