Use wantarray: 
sub test {
   print(defined(wantarray)?1:0, " ");
   print(wantarray?1:0, "\n");
}

test();       # 0 0
$a = test();  # 1 0
@a = test();  # 1 1

[download]
sub function {
   my $rv = "Hello World";

   if (defined wantarray) {
      return $rv;
   } else {
      print("$rv\n");
      return;
   }
}

function();              # Hello World

my $greet = function();
print("[$greet]\n");     # [Hello World]

[download]

In reply to Re: How much can a function know about the context in which it is called? by ikegami
in thread How much can a function know about the context in which it is called? by jacques

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