StackOverflow has had runnable snippets for a number of years. I notice the feature is absent from this site.
It's been noted that having source code in your question is okay here, so will this feature ever be implemented?
I don't see the need for that here.
While code is OK most questions won't include it because they don't need it. It seems to be overkill to enable something that will only be used on a handful of questions.