Is using $("#vacations").find("li").last()
is a better practice than $("#vacations li:last")
?
Background and my thoughts:
I was playing with a nice interactive try jQuery tutorial and one of the tasks says:
As you are looking through your code, you notice that someone else is selecting the last vacation with: $("#vacations li:last"). You look at this and you think, "Traversal would make this way faster!" You should act on those thoughts, refactor this code to find the last li within #vacations using traversal instead.
Why would I think so? For me usage of selectors looks a bit higher level than traversing. In my mind when I am specifying a selector it is up to jQuery how to better get the single result I need (without need in returning interim results).
What is that extra overhead of using composite selectors? Is it because current implementation of selectors logic just parses the string and uses the traversal API? Is parsing a string that slow? Is there a chance that a future implementation will use that fact that it does not need to return interim results and will be faster than traversal?
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