Re: moving in js

["João Távora" <joaotavora@gmail.com>]

> Single words and symbols also are not balanced expressions IMO.
> When on ba|z
>
> (foo (bar ba|z) quux)
>
> C-M-b would reach |baz
>
> (foo (bar |baz) quux)
>
> i.e, it would do backward-word

No, it's doing backward-sexp. "baz" happens to also be a sexp (an
atomic), and it's not a question of opinion (see below).

> a repeat would do backward-word again, a third would error
>
> Can't see any relation to stipulated move over balanced expression here.
>
> Looks fairly arbitrary.

It's not. In lisp-mode, where this is clearer (but as we have seen it
can and has been generalized to other programming modes), a word and a
symbol are also sexp's. See http://en.wikipedia.org/wiki/S-expression:
a sexp can be an atom or a list ( a . b ) where a and b are themselves
sexp's. As you have found, backward-word doesn't error,  because it
doesn't care about sexp's. But backward-sexp does :-) , indeed it
*must* error to tell you there are no more sexp's backwards at that
level.

IMO this is one of the best designed features in Emacs, and one many
non-Emacs users envy. When I move and delete with the C-M-* keys, I
get structured editing for free. And (shameless plug) if I add
autopair.el to that, I don't need paredit.el at all.  Furthermore,
because Emacs generalizes the sexp concept to other modes via
syntax-tables,  structured editing (and autopair) "just work" in
almost every programming mode that defines delimiters.

> CC to help, as it might be of some interest for others to.

of course, I forgot to send my previous message to the list.

-- 
João Távora