class Haml::Exec::Generic

def parse!

Calls `Kernel#exit` at the end, so it never returns.
Parses the command-line arguments and runs the executable. 
def parse!
  begin
    @opts = OptionParser.new(&method(:set_opts))
    @opts.parse!(@args)
    process_result
    @options
  rescue Exception => e
    raise e if @options[:trace] || e.is_a?(SystemExit)
    $stderr.puts e.message
    exit 1
  end
  exit 0
end