recover should send messages to stderr, not stdout

-----Original Message-----
From: Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk] 
Sent: Tuesday, May 11, 2004 11:21 PM
To: Vadim Ogranovich
Cc: R-Help
Subject: Re: [R] recover should send messages to stderr, not stdout

...

Note that some of us consider recover() to be designed for 
interactive-only use, and use something like

Unfortunately, R help doesn't reflect the apparent diversity of
opinions. Regarding recover it says

     The use of 'recover' largely supersedes 'dump.frames' as an error
     option, unless you really want to wait to look at the error.  If
     'recover' is called in non-interactive mode, it behaves like
     'dump.frames'.  <...>

    options(error=expression(if(interactive()) recover() else 
dump.calls()))

This is useful. Thank you very much for the tip!

On Tue, 11 May 2004, Vadim Ogranovich wrote:

recover() sends all its messages, which I consider to be error 
messages, to stdout. I think they more properly belong to stderr.
 
This is an important difference for those of us who use R in batch 
mode to generate ASCII files.

Only to the subset who believe that recover() is a useful 
error option in 
non-interactive use.

This subset is likely to include everyone who carefully reads the
documentation, see the above excerpt from a help page.