sub print_context {
    if (not defined wantarray) {
      print "[void context]";
    } elsif (wantarray) {
      print "[list context]";
    } else {
      print "[scalar context]";
    }
    return undef;
  }
  "Hello", print_context, "World\n";               # void context
  print "\n";
  "Hello " . print_context . "World\n";            # scalar context
  print "\n";
  print "Hello " . print_context . "World\n";      # scalar context
  print "\n";
  print "Hello", print_context, "World\n";         # list context
  print "\n";
  join print_context,                              # scalar context
    print_context, print_context;                  # both list context
  print "\n";