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.<<05-08	Wednesday, 10:30 IBM San Jose, Elephant>>
∂AIL Dr. John Williams↓IBM Research↓K52-282↓5600 Cottle Road↓San Jose, CA 95193∞

Dear Dr. Williamson:

	Thanks for the invitation to talk at IBM Research.  Here is
the abstract.

THE ELEPHANT ALGORITHMIC LANGUAGE

	Elephant (it never forgets) is a new proposed algorithmic language
(perhaps not a programming language) with two properties.  First, like a
Lucid program, an Elephant algorithm is a collection of statements in first
order logic which can be used directly to prove properties of the algorithm.
Unlike Lucid, Elephant algorithms refer directly to the time; i.e. each
variable in an Algolic program is replaced by a function of time in the
corresponding Elephant algorithm.  Second, Elephant algorithms can refer
directly to the past of variables, and it is up to the compiler to decide
what information in data structures has to be kept in order to achieve the
specified behavior.  Thus an Elephant reservation algorithm can specify that
a person has a reservation (for an Elephant ride) if he has successfully
made one and it hasn't been cancelled.  On the basis of the prescribed
input-output behavior, the compiler must decide that cancelled
reservations and unsuccessful attempts to reserve needn't be remembered.

	An Elephant compiler - none presently exists - will have to be
a heuristic program, and the utility of the language depends on whether
a good one can be written.  If it can, Elephant will be a very high level
language.

.sgn