block-syntax.pl

$ perl -wle 'sub foo (&$*) { print "@_"; } foo(sub {*STDOUT},"a", "b");'
CODE(0x2561da8) a b
$ perl -wle 'sub foo (&$*) { print "@_"; } foo {*STDOUT} "a", "b";'
CODE(0x184ed68) a b

# How do I from inside foo distinguish the calls, to treat the first param magically?

# print example:

$ perl -wle 'print sub{*STDOUT},"a", "b";'
CODE(0x1a78d70)ab
$ perl -wle 'print {*STDOUT} "a", "b";'
ab