I did ?"NULL at the command line and was lead to ?"NULL-class" and the
BasicClasses help page in the methods package.
getClass("NULL"), getClass("character") show that these objects are unrelated,
so a class union is the way to define a class that is the union of these. The
essence of the behav
Dear r-devel,
The doc of bquote doesn't describe what inputs are allowed in `..()`, it
says :
*terms wrapped in ..() are evaluated and spliced into a call.*
I think "terms" is not clear enough, it might make the user think that
several arguments are possible, and the fact that `..()` (and `.()`
Hi Martin,
Thankyou for your response.
I suspect that we're not going to agree on the main point.
Making it trivially simple (as say Java) to set slots to NULL.
So, I'll move on to the other points here.
***Note that cited text uses excerpts only.***
> setClassUnion("character_OR_NULL", c("cha
Answering to convey the 'rules' as I know them, rather than to address the
underlying issues that I guess you are really after...
The S4 practice is to use setOldClass() to explicitly treat an S3 character()
vector of classes as an assertion of linear inheritance
> x <- structure (sqrt (37), cl
It seems one of the primary reasons to use the S4 system is *to be strict
about types.*
IMO the documentation is quite clear on this point, if NULL is not a
subclass of character, which it isn't because inherits(NULL, "character")
is FALSE then everything is behaving exactly as expected and docume
