Problem

Build a PN interpreter that will work both interactively and in batch. In the former case, the nondeterminism of the model can be resolved by the user through a dialog. In the latter case, nondeterministic choices should be taken randomly, but the user should be able to give appropriate scheduling options, possibly on the basis of previous experiences, before the relevant command is executed. For instance, one could ask for "complete execution?" In this case, the interpreter should provide all firing sequences, up to a predefined point. Alternatively, one could start from an existing firing sequence and ask for a change in some firing choices to obtain a new firing sequence as a modification of the previous one.