You're asking what context the function is being called in. There are (basically) three contexts in Perl - void, scalar and list. You can use the wantarray function to determine how your function has been called.

sub how {
  my $how = wantarray;
  if (defined $how) {
    if ($how) {
      print "list\n";
    } else {
      print "scalar\n";
    }
  } else {
    print "void\n";
  }
}

how;
my $s = how;
my @a = how;

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For your question I think you just need to check if the return value from wantarray is defined.

--
<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg

In reply to Re: subroutines & functions by davorg
in thread subroutines & functions by toonski

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