You mean these? Does it use them internally, because I haven't really seen them in any Svelte code.

If so, what does it matter what the compiler does in order to make your code work, so long as it's legal? It's perfectly valid JS, that's all that counts.

I wouldn't say Svelte is weird as much as it's different. That's the whole point after all. Instead of adding a bunch of library bloat and keeping an entire copy of the DOM to constantly compare to and derive changes from, it compiles your components down to native JS that manipulates the DOM directly, like you would by hand. Except of course the compiler uses different ways to achieve that than you would, but that's because it doesn't have to care about readability, as long as it creates valid and efficient code.