# Consumer Preference when Consumer only consumes $A$ or $B$

Let's say Sally either wants to coke or pizza, but never both.

I am aware of the standard consumer preferences, such as Perfect Complements as well as Perfect Substitutes.

But I have never heard of the above case regarding Sally. Is there a particular name for this preference type?

i.e. perhaps Sally wants a slice of pizza or Coke, and both cost \$1. She prefers the taste of Coke so she generally chooses it, but one day the price of Coke goes up to \$2. She may be satisfied to a similar degree purchasing pizza until the price of Coke comes back down. On a different day, she may want to purchase 2 pizzas for the same amount as 1 Coke. There are many possible outcomes with cross-category substitutes.