Emacs - Undefine Prefix Key

问题:

I somehow managed to define the 'M' (capital em) key as a prefix key in sqlplus-mode which is preventing me from typing an M.

How can I unset this prefix key in this mode?

回答1:

Short term fix:

M-x local-set-key M self-insert-command

Long term fix, find the spot in your .emacs file which defines it a ssuch. @tripleee's comment does sound like a likely candidate for what went wrong.