More work on symbolic sets.
More work on symbolic sets.

I think this as far as I go, until we know how they should be used.

diku-dk/futhark,ihc/futhark,diku-dk/futhark,HIPERFIT/futhark,ihc/futhark,diku-dk/futhark,HIPERFIT/futhark,diku-dk/futhark,mrakgr/futhark,HIPERFIT/futhark,mrakgr/futhark,diku-dk/futhark,mrakgr/futhark,CulpaBS/wbBach,ihc/futhark