Table 1.

Public Operations

Operation	Description
loadGuideline	Load a guideline represented by a text string conforming to the PROforma syntax.
evaluateExpression	Determine the value of a given PROforma expression
addDataValue	Change the value of a given data item.
confirmTask	Inform the engine that a given task has been performed.
commitCandidate	Commit to a particular candidate or candidates of a decision.
sendTrigger	Send a trigger to the engine. Triggers provide a means of explicitly starting tasks without waiting for their scheduling constraints to be satisfied.
setEngineTime	Set the engine time. As mentioned above the semantics does not require the engine time to correspond to any measure of “real world” time, but implementations of the engine will in general establish some such correspondence.
runEngine	Informally, the effect of the runEngine operation is to update the Properties Table so as to reflect the consequences of any previous operations that have been performed. For instance, if a task has been confirmed then the runEngine operation may cause other tasks to enter the in_progress state as a result of their scheduling constraints being satisfied. A more precise definition of this operation is given in the appendix.