Does this apply to the "open container law?

Most states now have laws pertaining to drivers and the open container law. this means its a violation of law for the driver to be behind the wheel with an open can or bottle of alcohol. it appears this law only applies to beer, so here is my question: what if the driver has a styrofoam cup filled with vodka and has a lid on the cup with a straw coming out the top? i know the answer, but i thought this would be a good question for maybe those people that do not know the answer. so, is this or is this not a law violation?