@top Document { heading line* }

heading { Heading? "\n" }
line    { Indent* ((AutoLink | word) space*)* "\n" }

@tokens {
  space       { $[ \t] }
  word        { ![ \t\n]+ }
  Heading     { ![\n]+ }
  Indent      { space }
  AutoLink    { ("http" | "https") "://" word }
  @precedence { AutoLink, word }
}