In my experience I would find myself frequently falling back to explicit brackets and more traditional Javascript syntax when I wasn't sure how to construct the statement. Which was okay (I wasn't stumped), but it happened fairly often. Your multiple line example (without "function") is the kind of thing I wouldn't be able to create on my own – both the indentation and comma have to be in just the right place, and the rules that govern that are not very clear. Or rather, it seems to be the one thing that works given a bunch of rules that are interacting in that particular situation. And each time I'd get something like that wrong it'd probably compile, but then I'd have to read the generated source to see what I'd actually done.