[CMake] xcodeproj internal reference lottery

[hauns at mac.com]

>Those id's are all over the place in projects.  But, sounds like the 
>only ones that need to persist are the ones that represent files.  I 
>suppose you could load in the existing project if there is one, and 
>populate a map of object id's for the files.  You would have to write a 
>parser for the crazy Xcode file format.  That would be the cleanest way 
>to do it, as the information is already on the disk.   As Dave 
>mentioned, we don't have any funding for this right now, but you can 
>clone CMake, and give it a try.  I can provide assistance if you want to 
>attempt this.
>
>Thanks.
>
>-Bill

isn't it easier to just query hash values from the file system( for files that exist on disk) as the xcodeproj is generated? for nonexistent files (build products) one has to find unique new ids - using the current method. that would save us the xcodeproj parsing bit.

what expert time/funding are we talking?