verifying function existance no longer works in PHP4

Hi,

I developed an application in PHP3, and now I want to use it under PHP4.

However one thing is broken. I didn't read anything about it in the
incompatibilities list, so I'll post it here.

This is the thing:

I want to be able to check if a class has a certain function. I usually
do this like this:

if (isset($myobj->display))
{
  $myobj->display();
}

In PHP3 this works, and the function is only called if the object has a
dispay function. But in PHP4, the isset always returns false.

The above is just a simple example. I also used to do this in PHP3,
which worked:

$funcname = $name."_display";
if (isset($myobj->$funcname))
{
  $myobj->$funcname(); // (variable function)
}

Is the fact that this doesn't work in PHP4 a known issue? And if it's a
feature that's no longer supported, what's the alternative?

Greetings,
Ivo

--
Ivo Jansch <[email protected]>
ibuildings.nl - information technology
http://www.ibuildings.nl