[R] No traceback available when using try(...)

[Edouard DUCHESNAY]

Hello,

1. The Situation :
------------------------
The stack traceback is not available when error ouccured in a try(....)
-- test.R --------------------------------
f<-function(a){
  return ( log(a) )
}
try(f("A"))
traceback()
-------------------------------------------

I get the following message :
> try(f("A"))
Error in log(x) : Non-numeric argument to mathematical function
> traceback()
No traceback available

I try to use tryCatch(...) instead, I could get the stack traceback (using the finally), 
but the R program stop.

2. My goal
--------------------
All I need is to prevent a error to stop a program (like try() does), print the traceback 
just after the try(....), and get the error message (geterrmessage()).


3. Question
-------------------
A) stack traceback is not available when error ouccured in a try is a normal behavior ?
B) Do you have any sugestion to fill my goal ?
C) If not is it a good idea to investigate around withRestarts(expr, ...) ?


Best regards


PS : My R Version 1.8.1  (2003-11-21)
-- 
Edouard Duchesnay                      Tel: +33 1 69 86 78 52
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