I've just committed some changes to R-devel which affect environments. Specifically:
- using NULL as an environment is now deprecated: use baseenv() instead. (baseenv() is already available in R 2.2.0, where it returns NULL. For most purposes it retains the same meaning in R-devel.) If you do use NULL, it will be converted to baseenv(), and a warning printed. For example: > f <- function(x) 1 > environment(f) <- NULL Warning message: use of NULL environment is deprecated > environment(f) <environment: base> There may be some places where I've missed putting the conversion in place, and use of NULL will cause an error; please let me know if you find any of those. The intention is that NULL will be usable with warnings through to the end of the 2.3.x releases. - baseenv() is no longer its own parent. Its parent is an empty environment, available as emptyenv(). - You can now create your own environment with emptyenv() as its parent. Searches for variables in such an environment will not automatically proceed to baseenv(), as searches do in current R releases. Duncan Murdoch ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
