On Thu, Nov 11, 2010 at 9:37 AM, Tal Galili <tal.gal...@gmail.com> wrote:
> 4) My real intention is to somehow change the "<-" operator (not simply the > assign). I am unsure as to how to do that. > 5) Are there any major pros/cons to the adding of such meta-data to objects? > (for example, excessive overhead on memory/performance) I had a go at doing (4) a few years back. The major problem I had was that if you do: y <- 1:10 x <- y with a <- operator that sets a timestamp then: identical(x,y) is FALSE. I implemented timestamping by adding an attribute to objects during assigment by modifying the C source, and then lots and lots of R's tests failed during build because identical things were no longer identical. Might be better to store your metadata in a separate object, .metadata in the global env perhaps? Then just do: .metadata[[name_of_thing]] = list(modified=Sys.time()) in your modified assign. Performance will only be a problem if your program is doing nothing else except fiddle with metadata, I reckon. Your program does do something useful, doesn't it? Barry ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
