50 Chapter 2 Representations for Classical Planning
The Action Description Language (ADL) representation, introduced by Pednault
[434, 435], proposes a trade-off between the expressiveness of general logical for-
malism and the computation complexity of reasoning with that representation, i.e.,
computing the transition function γ . Starting from UCPOP [436], several planners
[120, 142, 433, 438] were generalized to ADL or to representations close to ADL
that handle most of the extensions introduced in Section 2.4. These extensions have
been implemented in the PDDL planning language used in the AIPS (International
Conference on AI Planning and Scheduling) planning competitions [196, 387].
Syntactic constructs similar to our state variables have been ...