Denotational semantics of goto: An exit formulation and its relation to continuations
This paper discusses the problem of providing a definition for the "GOTO" statement within the framework of denotational semantics. The accepted approach to the problem is to use "Continuations". An alternative "Exit Formulation" is described in this paper. A small language is introduced which illustrates the difficulties caused by statements which terminate abnormally. For this language definitions based on both approaches are provided. A proof of equivalence of the two definitions is then given. In a closing discussion it is pointed out that continuations can define a wider class of languages than exits, although the latter have been shown to be adequate to define languages as complex as PL/I.