[R] Deparsing '...'

Matthew Dowle mdowle at concordiafunds.com
Thu Mar 2 18:40:26 CET 2006


That's even neater.  But when its called from within another function, this
happens, see below.  I was planning to call f something like 'getdots' and
use it in several functions that need to do this.

> f <- function(...) as.character(match.call())[-1]
> f(a,b,c)
[1] "a" "b" "c"
> g = function(x,...) f(...)
> g(x,a,b,c)
[1] "..1" "..2" "..3"


> -----Original Message-----
> From: Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk] 
> Sent: 02 March 2006 17:18
> To: Matthew Dowle
> Cc: 'r-help at stat.math.ethz.ch'
> Subject: Re: [R] Deparsing '...'
> 
> 
> f <- function(...) as.character(match.call())[-1]
> > f(x,a,b,c*d)
> [1] "x"     "a"     "b"     "c * d"
> 
> On Thu, 2 Mar 2006, Matthew Dowle wrote:
> 
> >
> > Hi,
> >
> > The following function works, but is there a neater way to write it?
> >
> > f = function(x,...)
> > {
> >    # return a character vector of the arguments passed in after 'x'
> >    gsub(" 
> > ","",unlist(strsplit(deparse(substitute(list(...))),"[(,)]")))[-1]
> > }
> >
> >> f(x,a,b,c*d)
> > [1] "a"   "b"   "c*d"
> >>
> >
> > Thanks.
> 
> -- 
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>




More information about the R-help mailing list