local323 external packages rtools

@kevinushey - I raised a few issues a while back about packrat not having a great story with compilation on windows.

This was around a number of packages such as XML, stringi, regal and others that had system dependencies that were required to build.

I've been looking into this and found that when you have the external goodies listed on CRAN here set up they build no problem.

The setup procedure was to download local323.zip, extract somewhere and edit makeconf files to point to folder. e.g the following where c:/extsoft is where I extracted the zip.

LOCAL_SOFT = c:/extsoft
LIB_XML = c:/extsoft

Note this is less manual than what is said in say the XML windows readme.

The only packages I've not got this to work for yet are Rcurl and curl which from the link look to have something their own system dependencies that I'll need to set up. Edit: downloading spatial zip in r goodies folder and extracting to same location builds these too.

Is there any way you can think of working this process into packrat or do you even think that's the best place to do so? I've tried with the majority of problem packages I'd previously identified and this seems to solve the compilation problem on windows for me.

Start by reviewing packrat's package installation and compilation flow, then compare it with the CRAN Rtools external goodies and the local323.zip setup described here. Check how packages such as XML, stringi, regal, Rcurl, and curl currently handle system dependencies. Done would require a defined, maintainable way for packrat to support this process, but the issue does not specify the intended design or tests.