How to debug functions they called via eval etc

Question

I dont know how to debug structures like:

fun1 <- function(obj){
   a<-c(obj,4)
   c(a,5)
}

fun <- function(obj){
   a <- match.call()
   a[[1L]] <- fun1
   return(eval.parent(a))
}

I would like to know how to instruct the debug-mode to follow the call eval.parent(a) and jump into fun1.

There's an awful lot of unnecessary code here. You will get better answers (and better understand the problem yourself) if you boil it down to a minimally reproducible answer: http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example — Ari B. Friedman, Jun 17 '12 at 11:26
I split up the most interesting part of my problem I hope that makes it easier to read it. — Klaus, Jun 18 '12 at 16:40

score 1 · Accepted Answer · answered Jun 18 '12 at 18:17

Per the debug help page: "If you want to debug a function not starting at the very beginning, use trace(..., at = *) or setBreakpoint."

> trace(eval.parent)

> fun(4)
trace: eval.parent(a)
[1] 4 4 5

Or perhaps you want to raise a warning and use that to trigger the browser. Hard to tell at this point what you are expecting.

1 Answers1