Multi-operational Apply

[SSoelvsten]

One peer reviewer for the TACAS 2022 submission on Adiar suggested to alter the Apply such that one can compute f O g for multiple binary operators O at the same time, e.g. f /\ g and f \/ g.

This should be possible as follows:

1. Run the Apply.
   • Disable pruning based on the operator. Or even better: prune only if all operators would prune the subtree.
   • For every pair of leaf values output both of them in an arc src -> (t1, t2) that includes both sink values.
2. For every operator O run the Reduce.
   • Whenever a sink-arc is pulled from a file, the operator is applied to it.

[SSoelvsten]

The main question to ask (the reviewer did too) is whether we can find a use-case for this?