class constructor force fail

[saraadmin]

Is it possible (in PHP4) to make some statement in a class constructor which causes the construction to fail and returns a null value to the expression which called:

$obj = new Class()

?

[mrhappiness]

class myclass {
  function myclass() {
    if (time() % 2)
      return NULL;
  }
}

$obj = new myclass();

[Installer]

Here's another test script you can run:

class Test
{
    function Test()
    {
        $this = null;
    }
}

$test_obj = new Test();
if (is_null($test_obj)) {
    echo '$test_obj is null';
}

[saraadmin]

I tried that but I didn't get a null value, just a normal object. (I even tried removing my conditional statement and having a constructor which just went "return null;" but I still got an object).

(I've actually altered another part of my code so that I don't need to be able to do this anymore but it would still be interesting to know if its possible...)

[saraadmin]

Sorry Installer, your reply came while I was still typing mine!

Yes, $this = null in the constructor does do the job. Good to know ;-)

[mtmosier]

But be forewarned, php5 doesn't allow you to change $this anymore.

[mrhappiness]

but using php5 you can throw an exception