Hi,
I have a question regarding setting options that use a list. There are
none that I'm aware of in R-base, however, it can make sense for some
custom situations. For example:
options(myoptions=list(lwd=1,density=NULL,angle=45,col="green"))
Getting values is simple:
getOption("myoptions")$col
However, setting a value from the list is less intuitive; here are a few
failed attempts that could make sense from an intuitive level:
setOption("myoptions")$col <- "red" # non-existing
function
options("myoptions")[[1]]$col <- "red"
Here is an attempt that almost works, but as documented, it only sets a
local .Options object for S-compatibility:
.Options["myoptions"][[1]]$col <- "red"
.Options["myoptions"][[1]]$col # works, but ...
getOption("myoptions")$col
The only method I know of is to modify a copy of the list from the
options, then re-set the option:
cp <- getOption("myoptions")
cp$col <- "red"
options("myoptions"=cp)
getOption("myoptions")$col
So, my question is if there is a more elegant method of setting an
option in a list, that doesn't need copying and multiple commands?
Having a 'setOption' function sure could be helpful for this instance,
however I'm unsure how to implement this method (or if it is possible in
the current version of R).
Thanks.
+mt