Having difficulty following the examples in John Chambers paper "Classes
and Methods in the S Language", dated 9 August 2001. See error below in
whatis (matrix (0,2,3)). Thanks for help.
> library (methods)
> whatis <- function (object) paste ("an object of class",
+ data.class (object))> setMethod ("whatis", "vector", function (object)
+ paste (data.class (object), "vector of length",
+ length (object)))
Creating a new generic function for "whatis" in package
.GlobalEnv
[1] "whatis"> whatIsMatrix <- function (object)
+ paste (data.class (as (object, "vector")), "matrix
with",
+ nrow (object), "rows and", ncol (object),
"columns")> setMethod ("whatis", "matrix", whatIsMatrix)
[1] "whatis"> whatis (matrix (0,2,3))
Error in paste(".", prefix, name, sep = "__") :
evaluation is nested too deeply: infinite
recursion?> R.version
_
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
status
major 1
minor 6.2
year 2003
month 01
day 10
language R