Jeff Atwood also has a very great writeup of something similar to this on his blog[1]

I also have something similar going on with my blog. It focuses on game development, so I actually embed an iframe with a canvas to let the users play around with the code as they learn.

I really think that interactive interfaces like this for blogs and tutorials will be more common place in the future.

[1]https://blog.codinghorror.com/our-programs-are-fun-to-use/