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Date: Mon, 16 Feb 2004 00:55:16 -0500
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Subject: extending interfaces - fringe behavior
From: hans@velum.net (Hans Lellelid)

I have a need in a current application to extend interfaces and possibly 
re-define (change signature) some of the inherited methods in the child 
interface.

e.g.

interface Foo {
	public function __construct(MyCls $var);
	public function myFunction();
}

interface Bar extends Foo {
	public function __construct(MyCls $var, $var2 = null);
	public function myOtherFunction();
}

class A implements Bar {
	public function __construct(MyCls $var, $var2 = null) {
		// ...
	}
	public function myFunction() {
		// ...
	}
	public function myOtherFunction() {
		// ...
	}
}

This is not currently possible in PHP5b4, due to the (new?) "Can't 
inherit abstract function" errors generated by the engine.  I.e. if I 
try to redefine __construct() I will get an error.

The need for this capability is probably not that mainstream, but it'd 
be very nice.  Is there any chance of having support for this behavior? 
  I don't know anything about the underlying mechanism for supporting 
interface extension, so I don't know if what I'm asking is trivial or not.

Thanks,
Hans