Re: Keep-only-column

[Marc Tfardy]

weber wrote:
> On 8 fev, 16:15, "weber" <hug...@gmail.com> wrote:
>> hello again!
>> Quite frequently I paste stuff which is space-separated.
>> I would really like a function that would let me select a region and
>> keep only a column, deleting all the rest.
>> Anyone knows how I could implement something like this?
>> I can do it with regexps, but then I have to come up with a new one
>> every time...
>> TIA
>> HS
>
> I think the format of "stuff" can't be understood from above :) Here
> it is:
>
> variable BLABLA  =     438438
> variable LABLAC  =     312
> variable DAUSH  =     43538
>
> Apply to that region: keep-only-column 2 makes it:
> BLABLA
> LABLAC
> DAUSHD



Here my draft. Probalby inefficient, but it does the job.


(defun trim-rectangle (start end)
  "Trims region to rectangle."
  (interactive "r")
  (save-excursion
    (let ((offset 0)
          (width 0)
          (lines (count-lines start end))
          (i 0))
      (goto-char start)
      (beginning-of-line)
      (setq offset (- start (point)))
      (goto-char end)
      (beginning-of-line)
      (forward-char offset)
      (setq width (- end (point)))
      (goto-char start)
      (while (< i lines)
        (beginning-of-line)
        (delete-region (point) (+ (point) offset))
        (forward-char width)
        (delete-region (point) (line-end-position))
        (end-of-line)
        (forward-char)
        (setq i (+ i 1))))))

HTH

regards

Marc