Publishers.Merge7
A publisher created by applying the merge function to seven upstream publishers.
Declaration
struct Merge7<A, B, C, D, E, F, G> where A : Publisher, B : Publisher, C : Publisher, D : Publisher, E : Publisher, F : Publisher, G : Publisher, A.Failure == B.Failure, A.Output == B.Output, B.Failure == C.Failure, B.Output == C.Output, C.Failure == D.Failure, C.Output == D.Output, D.Failure == E.Failure, D.Output == E.Output, E.Failure == F.Failure, E.Output == F.Output, F.Failure == G.Failure, F.Output == G.Output