[Rd] Is difftime a class

I am trying to write S4 methods with difftime in the signature but am being informed (? not a warning or error) that difftime is not a class. Nevertheless, dispatch takes place. Should I simply ignore that information? Here is a toy example: setClass(foo, contains = Date) setMethod(+, c(foo,

Re: [Rd] Is difftime a class

difftime is an S3 class, not an S4 class. To convert it, include the line setOldClass(difftime) and the setMethod call should work. On 7/9/2013 6:03 AM, Dan Murphy wrote: I am trying to write S4 methods with difftime in the signature but am being informed (? not a warning or error) that