We present a general semantic universe of call-by-value computation based on elements of game semantics, and validate its appropriateness as a semantic universe by the full abstraction result for call-by-value PCF, a generic typed programming language with call-by-value evaluation. The key idea is to consider the distinction between call-by-name and call-by-value as that of the structure of information flow, which determines the basic form of games. In this way the call-by-name computation and call-by-value computation arise as two independent instances of sequential functional computation with distinct algebraic structures. We elucidate the type structures of the universe following the standard categorical framework developed in the context of domain theory. Mutual relationship between the presented category of games and the corresponding call-by-name universe is also clarified.

The essential feature of this semantic representation of call-by-value computation is clean behavioural articulation of the concerned class of functional computation where categorical type structures and structures of interaction go hand in hand. The structure of interaction is representable as a specific form of name passing interactions, which is in close connection to Milner's encoding of call-by-value lambda calculus. This aspect will also be discussed, together with our recent development based on the present work, if the time allows.

(Nobuko Yoshida, first presented at ICALP'97, Bologna.)