elixir-lang/ex_doc — pull request #83 by ericmj (2013-10-09 14:40:01+00:00)
Title: Add lazy mix.exs options

Works for Ecto:

```elixir
defmodule Ecto.Mixfile do
use Mix.Project

def project do
[ app: :ecto,
version: "0.0.1",
deps: deps(Mix.env),
env: envs,
name: "Ecto",
elixir: "~> 0.10.3-dev",
source_url: "https://github.com/elixir-lang/ecto",
docs: fn ->
[ source_ref: System.cmd("git rev-parse --verify --quiet HEAD"),
main: "overview" ]
end ]
end
end
```

Also added support for string `:main` option so your main can be the readme or the overview.