Hugh's point is incredibly important. You don't really want one hundred thousand <option> elements in your DOM as your "auto-complete" solution.
To be honest, datalists are pretty worthless for every situation where I've needed to implement auto-complete functionality in projects, simply because the universe of possible entries has been always been huge.
To be honest, datalists are pretty worthless for every situation where I've needed to implement auto-complete functionality in projects, simply because the universe of possible entries has been always been huge.