As anyone who has read and understood wantarray knows, Perl has a notion of scalar versus list context, and you can do anything that you want with that hook. The question is what the most convenient default choice is.

Perl offers you little guidance in this. For instance in list context, localtime gives you a useful list, while in scalar it gives you a formatted result. Or caller will give you an array of information versus the single most likely to be useful fact, which happens to be the first element in the list. An array slice will give you the last element.

Here is a non-exhaustive set of choices that I have personally made in real code: 

# In these examples, @ret is your return in list context.
  return @ret;

  return wantarray ? @ret : \@ret;

  return @ret[0..$#ret];

  return wantarray ? @ret : $ret[0];

  if (wantarray) {
    return @ret;
  }
  elsif (1 == @ret) {
    return $ret[0];
  }
  else {
    croak("<function> did not produce a scalar return");
  }

# And for something completely different...
sub foo {
  if (1 != @_) {
    return map foo($_), @_;
  }
  # body of foo here.
  return $whatever;
}

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As you can see, I am hardly consistent. I also haven't thought deeply about this particular decision. (Truth to tell, my personal opinion is that the entire idea of context in Perl is an interesting experiment in language design that other languages have wisely decided not to borrow...) However it is an important choice, and I've been feeling that I shouldn't shortchange it as much as I have so far.

Therefore I am interested in which of the above (or other variations of your choice) people think is a good default behaviour to standardize on..and more importantly why.

Thoughts?

UPDATE: Removed typo in last example caught by converter. (I had a $ in front of foo.)

In reply to What should be returned in scalar context? by tilly

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