

   PPrriinntt CCaallll SSttaacckk ooff LLaasstt EErrrroorr

        traceback()

   DDeessccrriippttiioonn::

        `traceback()' prints the call stack of the last error,
        i.e., the sequence of calls that lead to the error.
        This is useful when an error occurs with an unidentifi-
        able error message.  Currently, this stack is given as
        a list in `.Traceback'.

   EExxaammpplleess::

        foo <- function(x) { print(1); bar(2) }
        bar <- function(x) { x + a.variable.which.does.not.exist }

        foo(2) # gives a strange error
        traceback()
        ## [1] "bar(2)" "foo(2)"
        bar
        ## Ah, this is the culprit ...

