Fixtype of statement outcomes.
This is a product type introduced by fty::defprod.
According to [Yul: Specification of Yul: Formal Specification], the execution of a statement results in not only possibly updated global and local states, but also a mode. [Yul: Specification of Yul: Formal Specification] does not have an explicit name for this notion, which in our formalization consists of a computation state and a mode. We call this a statement outcome.