What is the difference in key sequences between XEmacs and GNU Emacs?
Erik Naggum writes; Emacs has a legacy of keyboards that produced characters with modifier bits, and therefore map a variety of input systems into this scheme even today. XEmacs is instead optimized for X events. This causes an incompatibility in the way key sequences are specified, but both Emacs and XEmacs will accept a key sequence as a vector of lists of modifiers that ends with a key, e.g., to bind M-C-a, you would say [(meta control a)] in both Emacsen. XEmacs has an abbreviated form for a single key, just (meta control a). Emacs has an abbreviated form for the Control and the Meta modifiers to string-characters (the ASCII characters), as in `\M-\C-a’. XEmacs users need to be aware that the abbreviated form works only for one-character key sequences, while Emacs users need to be aware that the string-character is rather limited. Specifically, the string-character can accommodate only 256 different values, 128 of which have the Meta modifier and 128 of which have not. In each of t