A couple of days ago, I found
showexpl, it is wonderful and works very well. But there is one thing missing that it doesn't let me do and it is to only show the output/result of some commands. For little commands, there are no problems, a
minipage inside an
fbox works well, but for displaying titles and sections without affecting the number count in the document I have no idea how to do (except by embedded an image of the rendered document, which isn't that great of an idea).
For an example of what I am saying, I saw this a while ago while reading this tutorial (on page 4 there is an example of a document): https://dataninja.files.wordpress.com/2008/09/texpert2.pdf