[darcs-users] darcs --exact-config

[Thorkil Naur]

Hello,

On Monday 24 November 2008 15:18, Eric Kow wrote:
> On Mon, Nov 24, 2008 at 15:08:11 +0100, Salvatore Insalaco wrote:
> > What about a --exact-config flag that prints informations from GHC /
> > cabal / configure flags?

I totally agree that it would be great to get get this sort of information. In 
my dream-world, we would get both (1) what we asked for (via configure flags, 
environment variables, .cabal file contents, etc) as well as (2) what we 
actually got. I saw a tool recently that was able to report this sort of 
thing about itself, but I have tried in vain to recall which one it was.

In any case, now that we have targeted Cabal as our primary building 
mechanism, I don't think we should be modest and refrain from asking the 
Cabal-people for help on this matter. I guess that many others than darcs 
people could see such a function as valuable.

Technically, (1) what we asked for is some summary of configure options, 
environment, etc. Something that is certainly available and which could be 
incorporated into the executable and/or library we are building in some raw 
form. Quit easily, if allowed to remain raw. Somewhat more cumbersomely, if 
in a more neat and easier to digest form. For (2) what we actually got, I 
guess that some kind of linker map would contain the information, we are 
after, but also a lot of other details that we would prefer to be without. So 
I am not too sure here. In some cases, special-purpuse code inside darcs may 
have to be developed to support this. And in some cases, it may turn out to 
be impossible (so that we would basically have to say that we have asked for 
this, but we don't know what we actually got.).

And what we should not forget: In our libdarcs, this information should be 
available though a libdarcs function. (Just as we sit here and wish that, 
say, zlib or any other library that darcs uses provided a function that told 
us its version etc. Perhaps some of the libraries do already?)

> 
> It would be great to have something like this!
> http://bugs.darcs.net/issue849
> 
> -- 
> Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow>
> PGP Key ID: 08AC04F9
> 

Best regards
Thorkil