Two adjacent spaces and tabify

[Alan Mackenzie]

Hello, Emacs.

I have some elisp source on which tabify has been run.  This is fine and
good, but in many places in comments (and even strings), two spaces have
been replaced by a tab.  Even worse, in many other places, two spaces
have been replaced by tab, space.

With a tab-width of 8, one of these can be expected to occur every
fourth end of sentence, more or less.  This is not good.

It is easy enough to configure tabify such that only spaces at the
beginning of a line are candidates for tabs, but that might wipe out
desired tabs (for example, in commented out code).

Does anybody already have a solution for this problem, or any good ideas
on how to fix the current state (or even how to stop it happening in the
first place)?

Thanks!

-- 
Alan Mackenzie (Nuremberg, Germany).