On 2010 Dec 6, at 15:39, Jacek Generowicz wrote:
On 2010 Dec 6, at 14:15, Duncan Coutts wrote:
In the development version of cabal we have changed that error message to try and make it clear that it is looking for a program called pkg-config, not a Haskell package or a C lib.
cabal: The program pkg-config version >=0.9.0 is required but it could not be found.
Do you think that message would have helped avoid your confusion?
Oooh, that's a difficult question to answer, as I had read your earlier paragraph before coming to this question. After your explanation explained the error message (to the extent that I now wonder how on earth I ever took it to mean that it's looking for X11- xft version >=0.9.0, when it quite clearly states "pkg-config version >=0.9.0 is required but could not be found"), I have no idea whether the new message would have been better.
Is there an alternative message that would have been better?
Well, if I try to understand how I could have misunderstood the original message, I suspect that it is because of the common style of error message where the program generating the message precedes the actual message on the same line, just like "cabal: ..." precedes the message in this case. So I guess that I parsed it something like "... pkg-config: version >=0.9.0 is required ..." and inferred that 'version' refers to the package mentioned in an earlier message.
In which case, maybe something like
cabal: version >=0.9.0 of pkg-config is required ...
would have prevented me from making this particular mistake in this particular case.
Another thing that would probably have made it easier to understand: the message is strictly correct, but is *too* specific: it talks about pkg-config version >=0.9.0 not being found, while the problem was that *no version at all* was present. I would understand if making the error message change according to such subtle distinctions would be more effort that it is worth.