Contrasting Exceptions and Continuations
Hayo Thielecke · 2001
Exceptions and first-class continuations are the most powerful forms of control in programming languages. While both are a form of non-local jumping, there is a fundamental difference between them. We formalize this difference by proving a contextual equivalence that holds in the presence of exceptions, but not continuations; and conversely, we prove an equivalence that holds in the presence of continuations, but not exceptions. By the same technique, we show that exceptions and continuations together do not give rise to state, and that exceptions and state do not give rise to continuations.