Hello, I noticed that sys.frame treats which = 0 differently than sys.call and sys.function, and the documentation was unclear about it. > f <- function() sys.call() > f() f() > f <- function() sys.function() > f() function() sys.function() > f <- function() sys.frame() > f() <environment: R_GlobalEnv> sys.frame(0) always returns the .GlobalEnv, while sys.call(0) and sys.function(0) return the current call and function definition. I offer a patch to clarify this for the uninitiated. > sessionInfo() R version 2.6.0 Under development (unstable) (2007-04-16 r41194) i686-pc-linux-gnu locale: LC_CTYPE=en_US.UTF-8;LC_NUMERIC=C;LC_TIME=en_US.UTF-8;LC_COLLATE=en_US.UTF-8;LC_MONETARY=en_US.UTF-8;LC_MESSAGES=en_US.UTF-8;LC_PAPER=en_US.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US.UTF-8;LC_IDENTIFICATION=C attached base packages: [1] "stats" "graphics" "grDevices" "utils" "datasets" "methods" [7] "base" Jeff -- http://biostat.mc.vanderbilt.edu/JeffreyHorner -------------- next part -------------- A non-text attachment was scrubbed... Name: sys.parent.rd.patch Type: text/x-diff Size: 2406 bytes Desc: not available Url : https://stat.ethz.ch/pipermail/r-devel/attachments/20070417/248b1396/attachment.bin