Make the #'add-to-list implementation a little conciser and clearer for XEmacs 2008-05-14 Aidan Kehoe <kehoea@parhasard.net> * subr.el (add-to-list): Implement the same logic with a more concise syntax; thank you Stephen, in http://mid.gmane.org/87ablomdwx.fsf@uwakimon.sk.tsukuba.ac.jp .