# File lib/math_ml/latex.rb, line 131 def scan_option return nil unless scan(/\[/) opt = "[" p = pos-1 until (s=scan_any(true)) =~ /\A#{RE::SPACE}*\]\z/ opt << s if eos? self.pos = p raise OptionNotClosed end end opt << s self.pos = p _scan(/\A\[(#{Regexp.escape(opt[RE::OPTION, 1].to_s)})\]/) end