CodePage -> CodeBlock | DocBlock | CodePage

// lookahead 2 needed here
DocBlock -> DirectiveBlock | MarkdownBlock | DocBlock

DirectiveBlock ->
    <DOC_START> <DIRECTIVE_START> "author" RemainingLine EOL MarkdownBlock? |
    <DOC_START> <DIRECTIVE_START> "doc" RemainingLine EOL MarkdownBlock? |
    <DOC_START> <DIRECTIVE_START> "example" RemainingLine EOL MarkdownBlock? |
    <DOC_START> <DIRECTIVE_START> "org" OrgString EOL

MarkdownBlock -> MarkdownLine+

MarkdownLine ->
    <DOC_START> NOT_DIRECTIVE_START RemainingLine <EOL>

RemainingLine -> NOT_EOL*
Tokens
------

DOC_START -> "%%"
EOL       -> "\n"
NOT_EOL   -> ~"\n"
DIRECTIVE_START -> "@"
NOT_DIRECTIVE_START -> ~"@"