Traditionally this has been a problem for Ruby. There have been some
partial solutions published by different authors, but they all fall
short of the true GOF standard, posing some problems for their effective
use and implementation.
But, with Jackbox we overcome these problems and give a new spin to this
design pattern with Ruby. The Injector metaphor is the key, take a look
at this code: http://blog.jackbox.us/2015/09/decorators-in-scale.html