Re: How to do a massive unfill paragraph operation over several hundred files?

[Emanuel Berg]

Gerald Wildgruber wrote:

> Yes, that is the whole point I didn't
> understand! What does "ARGS" have to be when
> called non-interactively in a script.
> From the doc string of the function:
>
> (defun unfill-paragraph (&optional region)
>   "Takes a multi-line paragraph and makes it into a single line of text."
>   (interactive (progn (barf-if-buffer-read-only) '(t)))
>   (let ((fill-column (point-max)))
>     (fill-paragraph nil region)))
>
> I cannot see what to put here.

When you call that interactively what happens
is `barf-if-buffer-read-only', which

    [s]ignal[s] a `buffer-read-only' error if
    the current buffer is read-only

but if that doesn't hold (i.e. the buffer isn't
read-only), then "region", the optional
argument, is assigned `t'.

However when you call it from Lisp, NONE of
this happens so "region" remains nil!

Observe:

(defun test-interactive-optional-args (&optional arg)
  (interactive (progn (barf-if-buffer-read-only) '(t)))
  (message "arg: %s" arg) )
  
(call-interactively
#'test-interactive-optional-args)     ; arg: t

 (test-interactive-optional-args)     ; arg: nil
 
 (test-interactive-optional-args t)   ; arg: t

and of course:

 (test-interactive-optional-args nil) ; arg: nil

So in so many words, why don't you pass `t' as
the argument? :)

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