This question asks for an explanation of a snippet of code in an off-site resource.
If you take the off-site resource out of the question, the question is essentially:
Q: What does this syntax mean?
A: Nothing. It is not valid.
This does not seem to be a particularly useful question - somewhat akin to asking for a definition of a made-up word on one of the English language sites - and would probably be better as a comment on the original resource.
However, I can't see an applicable close reason for it (apart from 'Other', but then it doesn't seem to contravene any of the 'How to Ask' guidelines either). Previously, this might have fit under more general close reasons such as "not constructive" or "too localized."
Are such questions considered on-topic? If not, what is the convention for removing them? Downvote to oblivion?