Hi all,
Any insight into the code below would be appreciated - I don't
understand why two methods which I think should have equal distance
from the call don't.
Thanks!
Hadley
# Create simple class hierarchy
setClass("A", "NULL")
setClass("B", "A")
a <- new("A")
b <- new("B")
setGeneric("f", function(x, y) standardGeneric("f"))
setMethod("f", signature("A", "A"), function(x, y) "A-A")
setMethod("f", signature("B", "B"), function(x, y) "B-B")
# These work as I expect
f(a, a)
f(b, b)
setClass("AB", contains = c("A", "B"))
ab <- new("AB")
# Why does this return B-B? Shouldn't both methods be an equal distance?
f(ab, ab)
# These both return distance 1, as I expected
extends("AB", "A", fullInfo=TRUE)@distance
extends("AB", "B", fullInfo=TRUE)@distance
# So why is signature("B", "B") closer than signature("A", "A")
--
Chief Scientist, RStudio
http://had.co.nz/
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
