Io(Path, Error)

An IO operation (such as reading the Markdown file) failed.

The arguments of this case are:

1. The path of the file that couldn't be parsed
2. The IO error that occurred

FrontMatter(Path, FrontMatterError)

The JSON front matter is invalid.

The arguments of this case are:

1. The path of the file that couldn't be parsed
2. The error produced while parsing the front matter.

Markdown(Path, String)

The Markdown is invalid.

The arguments of this case are:

1. The path of the file that couldn't be parsed
2. An error message produced while parsing the Markdown

fn pub to_string -> String {
  match self {
    case Io(p, e) -> 'failed to read ${p}: ${e}'
    case FrontMatter(p, InvalidJson(m)) -> {
      'failed to parse the front matter of ${p}: ${m}'
    }
    case FrontMatter(p, m) -> 'failed to parse the front matter of ${p}: ${m}'
    case Markdown(p, v) -> 'failed to parse the Markdown of ${p}: ${v}'
  }
}

fn pub to_string -> String

Converts self to a String.