func WithBlacklist(b Blacklist) Option {
	return func(p *PubSub) error {
		p.blacklist = b
		return nil
	}
}
func WithBlacklist(b Blacklist) Option {
	return func(p *PubSub) error {
		p.blacklist = b
		return nil
	}
}
func WithBlacklist ( b Blacklist ) Option { return func ( p * PubSub ) error { p . blacklist = b return nil } }
// WithBlacklist provides an implementation of the blacklist; the default is a
// MapBlacklist
WithBlacklist provides an implementation of the blacklist ; the default is a MapBlacklist