Defines functions to be used by the several preprocessors as well as the behaviour they should have.

Preprocessors are the cornerstone of Still. A preprocessor chain can take a markdown file, execute its embedded Elixir, extract metadata from its front matter, transform it into HTML and wrap it in a layout.

There are a few defined chains by default, but you can extend Still with your own.

A custom preprocessor is simply a module that calls use Still.Preprocessor and implements the render/1function.

Take the following example:

defmodule YourSite.JPEG do
  use Still.Preprocessor

  @impl true
  def render(file) do
    file
  end
end

In this example, the render/1 function is used to transform the content and the metadata of a Elixir.Still.SourceFile.

See the preprocessor guide for more details.