* On Monday 2005-11-07 at 01:53:17 +0000, Julian Foad wrote: > Charles Levert wrote: > [...] > >Hence, my question was: is that the > >justification used by the POSIX committee when > >they standardized on this behavior for EREs? > > No. See the Open Group's rationale: > > http://www.opengroup.org/onlinepubs/009695399/xrat/xbd_chap09.html#tag_01_09_04 > > "It was suggested that, in addition to interval expressions, > back-references ( '\n' ) should also be added to EREs. This was rejected by > the standard developers as likely to decrease consensus." > > Presumably the lack of historical support for back-refs in ERE made it too > controversial.
Thanks for the pointer (and the answer). I was familiar with this whole reference (<http://www.opengroup.org/onlinepubs/009695399/>), but not with this Appendix in particular. Have you had the time to take another look at the [ef]grep patch? I have made a few small improvements since, but I don't want to submerge potential testers with too many versions.
