Generating documentation

Generating documentation from source code is done in two steps: generating a list of JSON files that contain documentation about symbols (e.g. classes and methods), and converting these JSON files into a desired format (e.g. a static website).

Writing documentation

Documentation is written using Markdown, specifically using the inko-markdown dialect.

Symbols (methods, classes, etc) are documented by placing one or more comments before them, without empty lines between the comments or between the last comment and the start of the symbol:

# This is the documentation for the constant.
# It happens to occupy two lines.
let NUMBER = 42

Modules are documented by placing comments at the start of the module:

# This is the documentation for the module.
import std.string (StringBuffer)

fn example {}

If the module documentation is followed by a symbol (e.g. a class), ensure there's an empty line after the comment, otherwise it's treated as the documentation for the symbol:

# This documents the _module_ and not the class.

class Example {}

The following can be documented:

  • Modules
  • Constants
  • Module methods
  • Classes
  • Traits
  • Methods defined on a class
  • Methods defined in an impl block
  • Methods defined in a trait

Generating the JSON files

Generating the JSON files is done by running inko doc in a project. The resulting files are stored in ./build/docs. For each module, a corresponding JSON file is generated. For example, the documentation for is stored in std_int.json.

The inko doc command also generates a $meta.json file that contains some additional information about the project, such as the contents of its README (if one is present).

Until Inko reaches version 1.0.0, the JSON structure of these files is unspecified and may change between releases.

Converting the JSON files

The JSON files themselves are not useful for users, so you'll need a tool to convert them to something useful.


idoc is a tool that converts these JSON files to a static website. Using idoc, you don't need to run inko doc yourself, instead you just run idoc in your project directory and the resulting static website is found at ./build/idoc/public.

idoc is installed as follows:

git clone
cd idoc
make install PREFIX=~/.local

This builds idoc and installs it into ~/.local, such that the executable is found at ~/.local/bin/idoc.

To document your project, run idoc inside your project directory. If ~/.local/bin isn't in your PATH variable, run ~/.local/bin/idoc instead.

idoc also provides a container that can be used with Docker and Podman:

# Using Docker:
docker pull
docker run --rm --volume $PWD:$PWD:z --workdir $PWD idoc:latest

# Using Podman:
podman pull
podman run --rm --volume $PWD:$PWD:z --workdir $PWD idoc:latest