From mboxrd@z Thu Jan  1 00:00:00 1970
From: Brian Wightman <MidLifeXis@wightmanfam.org>
Subject: Re: Not overwriting unchanged source code files when tangling
Date: Fri, 18 Nov 2011 11:14:29 -0600
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To: Tom Prince <tom.prince@ualberta.net>
Cc: Holger Hoefling <hhoeflin@gmail.com>, emacs-orgmode@gnu.org

On Fri, Nov 18, 2011 at 10:46 AM, Tom Prince <tom.prince@ualberta.net> wrot=
e:
> On Fri, 18 Nov 2011 08:23:18 -0600, Brian Wightman <MidLifeXis@wightmanfa=
m.org> wrote:
>> Perhaps a way to deal with this would be to tangle to a different
>> directory, and then sync any changes into your compilation source
>> directory. =A0If you would update the compilation directory only when
>> something differs from the tangle directory, then make could handle it
>> from that point on.
>
> The tangle mechanism could probably handle this autoatically. i.e. not
> saving a file if the contents are identical.

If there is not a lot of extra memory / time overhead associated with
this, I could see this being a valid approach.  I would request that,
if implemented, this be placed behind an on/off switch.

The makefile could also handle this with something along these lines
(correct the leading space -> tab conversion as well as proper macro
definitions):

tangleflag: totangle.org
   $(TANGLECOMMAND) totangle.org
   $(TOUCH) tangleflag

syncflag: tangleflag
   $(SYNCCOMMAND) sourcedir tangledir
   $(TOUCH) syncflag

--Brian