The sexp navigation in
js-mode that comes w/ Emacs 25.1.1 is broken,
so there is a quite popular
smartparens minor mode. All I
need from it is
(sp-up-sexp) w/ which it's possible to write "move
me to the beginning of the current expression", like
(define-key js-mode-map [(meta up)] (lambda () (interactive) (sp-up-sexp -1)))
(defun my-js-expr-start () "Requires smartparens." (while (sp-up-sexp -1)))
You don't have to turn
smartparens-mode on to use that.
Being curious of the internals of smartparens, I was "severely shocked" at its size. The main part the mode 327KB or, according to Github, 7133 SCLO.
7133 lines for a facility of auto-closing quotes, parens & whatnot!
This world is doomed for it'll collapse of its own bloat.