Inheritance

[Anon]

How much inheritance is supported in PHP?

i know you can extend classes, add extra functions to an existing class, that is documented. How about overwriting a preexisting function? Is that allowed?

For example:

class A {
function display() {
...
}
}

class B extends A {
function display() {
... // something different
}
}

[Anon]

I guess what I'm really asking about is abstract classes, like in C++, with virtual functions, etc... where inherited classes must implement...