Getting traceback in custom error handler in R -

i have function stop loaded library lib. replace default error handler in r function using options(error = stop). within function, traceback may display calls leading error being thrown. however, sys.calls not seem work within custom error handler. returns single element, is body of stop rather call. may have how r intercepts error handler stop. furthermore, traceback not work within stop. there way can proper traceback in custom error handler?

this works me:

> fun <- function(x) stop('hello') > stop <- function() print(sys.calls()) > options(error=stop) > fun(1) error in fun(1) : hello [[1]] fun(1)  [[2]] stop("hello")  [[3]] (function ()  print(sys.calls()))() 

this on r 3.1.2. doing different?