我可以根据命令行输入为gem指定动态依赖项吗？

Intro: I'm working on a gem that, by default, will pull information out of some XML data and do some sort of processing on the document. I'm using nokogiri to parse the XML. However, I wish to allow the user to parse the XML themselves and pass in the necessary information for my data processing methods to run, in case they don't want to install nokogiri or have already parsed the XML.: I'm working on a gem that, by default, w