Stefan Monnier <monnier@iro.umontreal.ca> writes:

>>     +          (if (= (/ end-col tab-width) (/ beg-col tab-width))
>>     +              ;; The spacing does not straddle a TAB boundary, so we won't
>>     +              ;; be able to use a TAB here anyway: there's nothing to do.
>>     +              nil
>
>> This detects a case where no tabs can be used.
>> It doesn't detect the case where tabs already ARE used.
>
> Those cases aren't matched by the regexp.
>
>>     -(defvar tabify-regexp "[ \t][ \t]+"
>>     +(defvar tabify-regexp " [ \t]+"
>
>> Is that change supposed to exclude those other cases?
>
> Exactly.
>
>         Stefan

IIUC,  your  patch does  work  and is  very  much  clearer than  mine.
However, it suffers from the same precondition on tabify-regexp, which
should be described in its docstring.

Thanks!

-- 
 |      Michaël `Micha' Cadilhac   |  Si les religions etaient aussi tole-  |
 |         Epita/LRDE Promo 2007   |  rantes qu'elles le pretendent, il y   |
 | http://www.lrde.org/~cadilh_m   |  a longtemps qu'il n'y en aurait plus  |
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