darcs patch: fix #1839, #1463, by supporting ghc-pkg bulkqueries with substring matching

[Simon Marlow]

Claus Reinke wrote:
>> I agree with it: I think we want the functionality, we don't want to add
>> a dep on a regex library, and using anything other than * for a wildcard
>> would be confusing. I can't remember the details of the various Windows
>> behaviours off the top of my head, so I can't comment on what the best
>> solution would be.
> 
> sigh. i was afraid you might say that.
> 
> ok, i've hacked up a proof of concept that seems to behave as well as 
> can be expected under these conditions,
> switching off default globbing and using an extra program, glob (which 
> just echoes its argument, after standard windows filename globbing), to 
> get controlled globbing.
> 
> now, the question is: where do we want to allow filename globbing in 
> ghc-pkg? the following involve files:
> 
>    register, update, FlagGlobalConfig, FlagConfig
> 
> but all of these seem to expect exactly one file, to be stored in a 
> single FilePath? am i missing something,
> or was this a wild goose chase?-)

Just turn off self-globbing for ghc-pkg.  Anyone using a sensible shell 
(i.e. bash) will still get globbing anyway.  I'd be surprised if anyone at 
all notices.

Cheers,
	Simon