Evaluate nearest expression, a bit like lisp's C-x C-e

[torbjorn]

Hi, in lisp I can go to the end of a bracket (foo bar)<-here and hit C-x C-e and it will evaluate the list that ends with that bracket

Could something similar be implemented for R?

Im thinking along these lines:

foo <- sum( is.na( some.funcion() ) ) )

If I place the marker after a bracket, it would evaluate the nested code matching that level, ie (showing the marker with underscore):

foo <- sum( is.na( some.function()_ ) ) # would evaluate some.function()

foo <- sum (is.na( some.fun_ction() ) ) # would also evluate some.function()

foo <- sum( is.na( some.function() ) )_ # would evaluate sum( ... )

foo <-_ sum( is.na(some.function() ) ) # would evaluate the assignment (and the sum )

That way I could easily debug nested code on one code line (or paragraph) without having to re-select incremently larger potions of it before running ess-eval-region

[torbjorn]

(in parentheses remarked, that last request should have said "parentheses" where it said "brackets")

[vspinu]

Thanks, this is indeed a very good suggestion. I am also missing it quite a lot, but never got down to actually implementing it.

[torbjorn]

Are there no lisp-heads that could get around to make this dream come true?

[jabranham]

@lionel- I see you assigned this to yourself a while ago. Have you ever gotten around to looking at how hard this would be to implement?

This came up in the Emacs subreddit recently and I felt bad saying no it's not possible but we have a 5 year old feature request for it :-(

[lionel-]

I'm working on it (and other things requiring the same feature) slowly when I find time. But I was sidetracked with other ESS things recently.

[vspinu]

C-u M-C-x would also be nice for instrumentationr. I keep pressing it instinctively.

[jabranham]

I'm removing this (commented) code in #721, perhaps it's useful here:

;; Experimental - after suggestion from Jenny Brian for an 'eval-multiline'
;; 'sentence' is too much : almost like 'paragraph'
;; 'sexp'     is close, but too little [when point is inside function call;
;;         it moves all the way to the end - which is fine]
(defun ess-eval-sexp (vis)
  "Send the current sexp to the inferior ESS process.
Prefix arg VIS toggles visibility of ess-code as for `ess-eval-region'."
  (interactive "P")
  (save-excursion
    (forward-sexp)
    (let ((end (point)))
      (backward-sexp)
      (ess-eval-region (point) end vis "Eval sexp"))))