# File lib/asciidoctor/parser.rb, line 1674
  def self.is_single_line_section_title?(line1)
    first_char = line1 ? line1.chr : nil
    if (first_char == '=' || (Compliance.markdown_syntax && first_char == '#')) &&
        (match = AtxSectionRx.match(line1))
      single_line_section_level match[1]
    else
      false
    end
  end