# File lib/asciidoctor/lexer.rb, line 1309
  def self.is_single_line_section_title?(line1)
    if !line1.nil? && (line1.start_with?('=') || (COMPLIANCE[:markdown_syntax] && line1.start_with?('#'))) &&
        (match = line1.match(REGEXP[:section_title]))
      single_line_section_level match[1]
    else
      false
    end
  end