- From: Stephen R. Savitzky <steve@crc.ricoh.com>
- Date: 28 Jul 1998 09:37:19 -0700
- To: keshlam@us.ibm.com
- Cc: www-dom@w3.org
keshlam@us.ibm.com writes: > I think I second Steve on this one. Nothing wrong with a null parent > pointer; it's easier for code to deal with that than to deal with an > implicit non-null. There's actually a good reason to _require_ null as the parent of an orphan node, and that is so that one can reliably determine whether a node is an orphan (and therefore safe to insert into a tree without cloning). It would be sufficient, though, to specify that orphan nodes have an unambiguously-determined value for their parent, since in some languages it's better to have an actual object as the parent than a null. Another possibility would be to throw an exception when trying to obtain the parent of an orphan node, but this would be less efficient and lead to clumsier code. Far better to simply require orphan nodes to have null as their parent. The third possibility is to add an "isOrphan()" method. This may be best, since it avoids even looking at the parent, which might (according to the present spec) have to create a fragment. -- Stephen R. Savitzky Chief Software Scientist, Ricoh Silicon Valley, Inc., <steve@rsv.ricoh.com> California Research Center voice: 650.496.5710 fax: 650.854.8740 URL: http://rsv.ricoh.com/~steve/ home: <steve@starport.com> URL: http://www.starport.com/people/steve/
Received on Tuesday, 28 July 1998 12:33:18 UTC