[Rd] is class2 Parameter's Documentation is Ambiguous

Dario Strbenac d@tr7320 @end|ng |rom un|@@ydney@edu@@u
Tue Aug 16 12:00:04 CEST 2022

Good day,

It appears that class2 needs to be of length 1.

> is(4, c("data.frame", "DataFrame"))
Error in is(4, c("data.frame", "DataFrame")) : 
  length(class2) == 1L is not TRUE

However, the documentation is "class1, class2: character strings giving the names of each of the two classes between which is relations are to be examined"

Also, class1 is not a parameter of the is function. It is a parameter of the extends function. I think the mention of "is relations" is unintended. Can the documenation be rewritten to remove the ambiguity for these?

Dario Strbenac
University of Sydney
Camperdown NSW 2050

More information about the R-devel mailing list