DB<40> sub my_say (;\@$$$) { dd \@_ }

  DB<41> my_say @a
[["a1", "a2", "a3"]]

  DB<42> my_say @a,$a
[["a1", "a2", "a3"], "A"]

  DB<43> sub tst (@) { dd @_ }

  DB<44> tst @a
("a1", "a2", "a3")

  DB<45> tst @a,2
("a1", "a2", "a3", 2)