gistfile1.rb

def make_monitor(opts={})
  classname_regex = opts[:class_name] || /.*/i
  method_regex = opts[:method_name]   || /.*/i 
  monitor = proc { |event, file, line, method, binding, classname|
    if (event.to_s =~ /call|return/i)
      if method.to_s =~ method_regex 
        if classname.to_s =~ classname_regex
          printf "%8s %s:%-2d %10s %8s\n", event, file, line, method, classname
        end
      end
    end
  }
  return monitor
end

def set_monitor(monitor)
  set_trace_func(monitor)
end

def unset_monitor
  set_trace_func nil
end