Re: How to remove the "read-only" property...

[Visuwesh <visuweshm@gmail.com>]

[ஞாயிறு ஆகஸ்ட் 28, 2022] Davin Pearson wrote:

>
> I have written some code that makes the first line read-only:
>
> (save-excursion
>   (goto-char (point-min))
>   (set-text-properties (point-at-bol) (point-at-eol) '(read-only t))
>   )
>
> When I try to remove all text-properties:
>
> (condition-case err
>     (save-excursion
>       (set-text-properties (point-min) (point-max) nil))
>   (error
>    (message "dmp-error:err=%s" err)))
>
> It barfs with the following error message:
>
> dmp-error:err=(text-read-only)
>
> How do I go about removing the read-only property of the text?

‘read-only’
     If a character has the property ‘read-only’, then modifying that
     character is not allowed.  Any command that would do so gets an
     error, ‘text-read-only’.  If the property value is a string, that
     string is used as the error message.

     Insertion next to a read-only character is an error if inserting
     ordinary text there would inherit the ‘read-only’ property due to
     stickiness.  Thus, you can control permission to insert next to
     read-only text by controlling the stickiness.  *Note Sticky
     Properties::.

     Since changing properties counts as modifying the buffer, it is not
     possible to remove a ‘read-only’ property unless you know the
     special trick: bind ‘inhibit-read-only’ to a non-‘nil’ value and
     then remove the property.  *Note Read Only Buffers::.

From (info "(elisp) Special Properties")