Which pattern should I use for my unique instance of the User class?

Question

I have this User class

class User{
  private    $logged = false;
  private    $id;

  public function User() {
      //> Check if the user is logged in wi         


        

Answer 1

Singletons are not evil. Bad usages of singletons are evil. The reason people have come to dislike this pattern so much (even going to the extent of calling it an anti-pattern, whatever that is), is due to improper use:

Too many inexperienced people make a class a singleton when they find they don't need more than one instance of a class. But the question isn't if you need only a single instance of the class, but whether more than one instance would break your code. So ask yourself this question: would your code break if there were more User instances? If not, then maybe you shouldn't bother. :)

There are legitimate uses of singletons. There are those people who fear this pattern like the plague and consider it always to be bad, without realizing that sometimes it can be very helpful. In the words of a much more experinced programmer than me, "singletons are like morphine: they can give you a real boost, but use them the wrong way and they an become a problem themselves". If you want me to go into some details as to when singletons could be a good choice, leave a comment to this answer. :)