DB<32> sub my_say (;&) { $_[0] ? say $_[0]->() : say $_ }

  DB<33> @a=('a1'..'a3'); $a="A",$b="B"; $_=666

  DB<34> my_say
666

  DB<35> my_say {@a}
a1a2a3

  DB<36> my_say {@a,$a}
a1a2a3A

  DB<37> my_say {$a,1..3}
A123

  DB<38>