A wrapper to extract the AST from a call to EarmarkParser.as_ast if a tuple {:ok, result, []} is returned, raise errors otherwise

iex(1)> as_ast!(["Hello %% annotated"], annotations: "%%")
[{"p", [], ["Hello "], %{annotation: "%% annotated"}}]

iex(2)> as_ast!("===")
** (Earmark.Error) [{:warning, 1, "Unexpected line ==="}]

This is a convenience method to read a file or pass it to EEx.eval_file if its name ends in .eex

The returned string is then passed to as_html this is used in the escript now and allows for a simple inclusion mechanism, as a matter of fact an include function is passed

A utility function that will be passed as a partial capture to EEx.eval_file by providing a value for the options parameter

    EEx.eval(..., include: &include(&1, options))

thusly allowing

  <%= include.(some file) %>

where some file can be a relative path starting with "./"

Here is an example using these fixtures

iex(3)> include("./include/basic.md.eex", file: "test/fixtures/does_not_matter")
"# Headline Level 1\n"

And here is how it is used inside a template

iex(4)> options = [file: "test/fixtures/does_not_matter"]
...(4)> EEx.eval_string(~s{<%= include.("./include/basic.md.eex") %>}, include: &include(&1, options))
"# Headline Level 1\n"