Actually, I personally did not think of this suggestion as being related to pattern matching, but instead being all about the aesthetics; having a clean way to split arguments to a macro over several lines. That it shares some features with pattern matching is to me tangential. Having a “line continuation” character could achieve the same purpose, but I personally don’t know which character should be used for this and I am not super fond of how it reads (e.g., \ in Python).