- From: Claude Zervas <claude@utlco.com>
- Date: Mon, 17 Aug 1998 20:56:39 -0700
- To: Ray Whitmer <ray@imall.com>, www-dom@w3.org
>> It is impossible to implement Node.append/insertChild() etc. without >> casting the Node argument to a known implementation. Otherwise, >> how would you set the parent and next/previousSibling attributes >> of the new child? Casting is slow (in Java) and it assumes a homogeneous >> implementation. > >It is a simple virtual function. The implementation supplies the >functionality, and the base class provides the API -- no expensive upcasting >involved at all. OO languages would be in big trouble if you had to upcast >every time you wanted to implement this type of a function. Hmmm, according to the latest spec Node.next/previousSibling are read-only. How do you set these without casting to an implementation that has set methods for these attributes if there are none in the interface ? I think maybe you thought there was Node.setNext/PreviousSibling() methods defined somewhere. This, as I understand, was a typo in the old spec. If not, then the latest spec isn't quite fully cooked. - Claude
Received on Monday, 17 August 1998 23:47:39 UTC