Clearly, you just memorise / know everything. Jokes aside, there is a balance to be had between having to look up trivial, everyday things via intellisense, and expecting people to know every single method on a massive set of libraries. I'm always surprised by people who claim that the latter approach is a good investment of their time and mental capacity. At some scale, it simply cannot be optimal.

>At some scale, it simply cannot be optimal.

Time spent memorizing APIs is time that could be spent learning new problem solving techniques or interesting algorithms.

These folks have bad opportunity cost assessments. There's always some piece of knowledge more useful for memorization than an API function.

I think one problem is that some of these sorts of things always pop info up at you, instead of you the coder pressing a keystroke to have it help you.

There's 3 different models that happen:

1. Type in the entire thing

2. Type in a unique portion and ask it to autocomplete

3. On each keystroke, evaluate if the list of auto-popped-up completions to see if the one you want is quickly available yet.

Clearly the 3rd is slowest to interact with, and does not convey useful information for familiar interfaces.

If you do not know or cannot remember what the interface looks like, it might be a bit more useful, but gives you similar information as the 2nd above when you have little to autocomplete. But the 2nd option still leaves you in control of the coding flow instead of the system constantly interrupting you to ask you if it knows what you mean yet.