The Discoveries of Continuations

We give a brief account of the discoveries of continuations and related concepts by A. van Wijngaarden, A. W. Mazurkiewicz, F. L. Morris, C. P. Wadsworth, J. H. Morris, M. J. Fischer, and S. K. Abdali. In the early history of continuations, basic concepts were independently discovered an extraordinary number of times. This was due less to poor communication among computer scientists than to the rich variety of settings in which continuations were found useful: They underlie a method of program transformation (into continuation-passing style), a style of definitional interpreter (defining one language by an interpreter written in another language), and a style of denotational semantics (in the sense of Scott and Strachey). In each of these settings, by representing “the meaning of the rest of the program” as a function or procedure, continuations provide an elegant description of a variety of language constructs, including call by value and goto statements.