backward-sexpbackward-sexp is an interactive compiled Lisp function in `
lisp.el'. It is bound to <C-M-left>, C-M-b, ESC <C-left>.
(backward-sexp &optional ARG) Move backward across one balanced expression (sexp). With ARG, do it that many times. Negative arg -N means move forward across N balanced expressions. This command assumes point is not in a string or comment. Uses `forward-sexp' to do the work.