Michael Kifer writes: > This was an update from the emacs tree and I did not check that XEmacs' > version of require does not take the third argument. Rather than changing > it in ediff, would not it be a good idea to sync requite with emacs? It > has an optional third argument, noerror. I think it would be a good thing. The three-argument require is already in 21.5. We continue to support 21.4, but it is supposed to be stable; API changes in general should not be made. A recent survey at a large Emacs-using shop showed that about 10% of users of Emacsen are using unsupported versions as of October 2007, this probably jumped to 30% with the release of Emacs 22.1 (this shop is a heavy user of XEmacs, in others it would probably be much higher). About 40% were not using the latest release of the version they use.