PP.Unifier
Node unifier
type unifier = node -> node -> node option
Unifier heuristic: given two nodes return None iff they don't unify, or Some x iff they unify as x
node
None
Some x
x
val unify : ?unify:unifier -> node list -> node list
Attempt to reduce the set of nodes by unifying multiple nodes into a single one.
additional unifier heuristics