R Classes and Methods for Spatial Data.
Before sp is loaded,
options("sp_evolution_status") may be set to
0L for legacy behaviour,
1L for setting
CRS(, doCheckCRSArgs=FALSE, ) and other minor steps to block calls out to rgdal etc., and
2L to use sf internally (not completed yet). If this option is not set, the environment variable
_SP_EVOLUTION_STATUS_ can be used, again before sp is loaded, set to
"2"; this is used for running revdep checks under different evolution scenarios, anticipating retirement of maptools, rgdal and rgeos.