* 2022-09-05 07:15:50+0300, Jean Louis wrote:

> Starting function to join lines is this one:
>
> (defun join-lines ()
>   "Joins lines of a paragraph of 100000 chars."
>   (interactive)
>   (let ((old fill-column))
>     (setq fill-column 100000)
>     (fill-paragraph nil)
>     (setq fill-column old)))

Not answering your actual question but I noticed that the above function
can be simplified because fill-column is a dynamic (special) variable:

    (defun join-lines ()
      "Joins lines of a paragraph of 100000 chars."
      (interactive)
      (let ((fill-column 100000))
        (fill-paragraph)))

-- 
/// Teemu Likonen - .-.. https://www.iki.fi/tlikonen/
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