bug#25992: perform-replace leaves mark-active when not transient-mark-mode

[Keith David Bershatsky]

Thank you very much for the suggestion to check 'mark' prior to calling either 
'region-beginning' or 'region-end', as an alternative to testing the variable 
'mark-active'.

Keith

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DATE:  Mon, 06 Mar 2017 20:45:32 +0200
FROM:  Eli Zaretskii <eliz@gnu.org>
> 
>  transient-mark-mode
> 
> > Date:  Mon, 06 Mar 2017 09:06:56 -0800
> > From:  Keith David Bershatsky <esq@lawlist.com>
> > Cc:  25992@debbugs.gnu.org
> > 
> > In a custom test to determine whether the region is active, I had been 
> > testing mark-active prior to using (region-beginning) and/or (region-end) 
> > to avoid trowing an error "The mark is not set now, so there is no region". 
> >  When the following is true `(and mark-active (= (region-beginning) 
> > (region-end)))`, my custom function should return nil.
> 
> Why can't you just check whether the function 'mark' returns nil?