R help - Oct 2012 - Completely ignoring an error in a function...

The code base is a bit too complicated to paste in here, but the gist of my
question is this: given I have a function

myfunction <- function(x)
{
# Do something A
# Do something B
# Do something C
}

Say "#Do something B" returns this error:
Error in cat(list(...), file, sep, fill, labels, append) :
  argument 2 (type 'list') cannot be handled by 'cat'

A standard function would stop here.  HOWEVER, I want, in this odd case, to
say "keep going" to my function and have it proceeed to # Do something
C.
 How do I accomplish this?  I thought suppressWarnings() would do it but it
doesn't appear to.

Assume that debugging "Do something B" is out of the question.  Why am
I
doing this?  Because in my odd case, "Do something B" actually does
what I
needed it to, but returned an error that is irrelevant to my special case
(it creates two files, failing on the second of the two files -- but the
first file it creates is what I wanted and there is no current way to
create that single file on its own without a lot of additional coding).

--j

-- 
Jonathan A. Greenberg, PhD
Assistant Professor
Department of Geography and Geographic Information Science
University of Illinois at Urbana-Champaign
607 South Mathews Avenue, MC 150
Urbana, IL 61801
Phone: 217-300-1924
AIM: jgrn307, MSN: jgrn307@hotmail.com, Gchat: jgrn307, Skype: jgrn3007

	[[alternative HTML version deleted]]

I'd wrap it in try() - the failing function will run, and you can
check after the fact whether it failed or not.

Sarah

On Wed, Oct 17, 2012 at 3:48 PM, Jonathan Greenberg <jgrn at illinois.edu>
wrote:
> The code base is a bit too complicated to paste in here, but the gist of my
> question is this: given I have a function
>
> myfunction <- function(x)
> {
> # Do something A
> # Do something B
> # Do something C
> }
>
> Say "#Do something B" returns this error:
> Error in cat(list(...), file, sep, fill, labels, append) :
>   argument 2 (type 'list') cannot be handled by 'cat'
>
> A standard function would stop here.  HOWEVER, I want, in this odd case, to
> say "keep going" to my function and have it proceeed to # Do
something C.
>  How do I accomplish this?  I thought suppressWarnings() would do it but it
> doesn't appear to.
>
> Assume that debugging "Do something B" is out of the question. 
Why am I
> doing this?  Because in my odd case, "Do something B" actually
does what I
> needed it to, but returned an error that is irrelevant to my special case
> (it creates two files, failing on the second of the two files -- but the
> first file it creates is what I wanted and there is no current way to
> create that single file on its own without a lot of additional coding).
>
> --j

-- 
Sarah Goslee
http://www.functionaldiversity.org

Have a look at example(try) and demo(error.catching)
> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at
r-project.org]
> On Behalf Of Jonathan Greenberg
> Sent: Wednesday, October 17, 2012 21:48
> To: r-help
> Subject: [R] Completely ignoring an error in a function...
> 
> The code base is a bit too complicated to paste in here, but the gist of my
> question is this: given I have a function
> 
> myfunction <- function(x)
> {
> # Do something A
> # Do something B
> # Do something C
> }
> 
> Say "#Do something B" returns this error:
> Error in cat(list(...), file, sep, fill, labels, append) :
>   argument 2 (type 'list') cannot be handled by 'cat'
> 
> A standard function would stop here.  HOWEVER, I want, in this odd case, to
> say "keep going" to my function and have it proceeed to # Do
something C.
>  How do I accomplish this?  I thought suppressWarnings() would do it but it
> doesn't appear to.
> 
> Assume that debugging "Do something B" is out of the question. 
Why am I
> doing this?  Because in my odd case, "Do something B" actually
does what I
> needed it to, but returned an error that is irrelevant to my special case
(it
> creates two files, failing on the second of the two files -- but the first
file it
> creates is what I wanted and there is no current way to create that single
file
> on its own without a lot of additional coding).
> 
> --j
> 
> --
> Jonathan A. Greenberg, PhD
> Assistant Professor
> Department of Geography and Geographic Information Science University of
> Illinois at Urbana-Champaign
> 607 South Mathews Avenue, MC 150
> Urbana, IL 61801
> Phone: 217-300-1924
> AIM: jgrn307, MSN: jgrn307 at hotmail.com, Gchat: jgrn307, Skype: jgrn3007
> 
> 	[[alternative HTML version deleted]]
> 
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