When is asking, asking out?

This is one of those, "You'll know it when it happens to you"-type situations.
But doesn't it itch so much to know if you've just been asked to have lunch or whether that lunch is in fact, a date?
Perhaps the nature of how the question was asked and any possible inklings could try and answer that question whose answer only lies in the future. It's a delicious, tantalizing ambiguity (I took a little from Gilda Radner there). But it's not too difficult to forget how anooying it is to not know!!!