# File lib/rcov/lowlevel.rb, line 137
    def self.format_backtrace_array(backtrace)
      backtrace.map do |line|
        md = /^([^:]*)(?::(\d+)(?::in `(.*)'))?/.match(line)
        raise "Bad backtrace format" unless md
        [nil, md[3] ? md[3].to_sym : nil, md[1], (md[2] || '').to_i]
      end
    end