Turbo Prolog

list A special sort of object consisting of a collection of elements enclosed in square
brackets and separated by commas.
message window The window in which messages related to the operation of the
Turbo Prolog system appear.
module A Turbo Prolog program with global declarations forming part of a project.
multiple predicate declarations Anyone predicate can have several declarations,
each involving different domain specifications for the argument(s) of the relevant
relation.
name Any contiguous sequence of letters, digits, and underscore characters that start
with a lowercase letter or underscore.
object The name of an individual element of a certain type.
operator priority The hierarchy that determines the order in which operators are
obeyed in arithmetic expressions.
parameters Collective name for the objects and variable names in a relation.
pointer The device by which Turbo Prolog keeps a record of the next place in its
database of facts and rules to which to backtrack.
predicate Every Turbo Prolog fact or rule belongs to some predicate, which specifies
the name of the relation involved and the types of objects involved in the relation.
project A Turbo Prolog program consisting of more than one module.
real A decimal number in the range ± I.OE- 307 to ± I.OE+ 308.
recursion The technique whereby an entity is defined in terms of itself.
reference objects and domains If an unbound variable is passed from one sub-goal to
another, the domain containing the values to which the variable will eventually become
bound must be declared as a reference domain. Elements of such a domain are reference
objects.
relation A name describing the manner in which a collection of objects (or objects
and variables referring to objects) belong together.
repeat . .fail combination A technique that can be used to avoid tail recursion by using
Turbo Prolog's backtracking mechanism instead.
return from a sub-goal (or predicate) An expression used to denote that Turbo
Prolog has now finished evaluating a certain sub-goal (belonging to the given predicate).
rule A relationship between a "fact" and a list of sub-goals which must be satisfied for
that "fact" to be true.
satisfying a sub-goal The process by which Turbo Prolog chooses values for any
unbound variables (if possible) in such a way that the sub-goal is true according to the
given clauses for the corresponding predicate.
search principle One of four basic rules that Turbo Prolog follows in attempting to
satisfy a goal.
stack The part of memory used by Turbo Prolog for parameter transfer.
stand-alone programs Programs that can be run from DOS independently of the
Turbo Prolog system.
standard predicate A predicate already defined internally in Turbo Prolog.
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