class Asciidoctor::Lexer

def self.section_level(line)

line - the String line from under the section name.

used in the ASCII line under the section name.
Private: Get the Integer section level based on the characters 
def self.section_level(line)
  char = line.strip.chars.to_a.uniq
  case char
  when ['=']; 0
  when ['-']; 1
  when ['~']; 2
  when ['^']; 3
  when ['+']; 4
  end
end