[Rd] Comments in the DESCRIPTION file

[William Dunlap]

Why not just use some tag that R doesn't already use, say "Comment:", instead
of a #?  If you allow # in position one of a line to mean a comment then people
may expect # to be used as a comment anywhere on a line.

(It may also mess up some dcf parsing code that I've written - it checks that lines
after tagged lines are either empty, the start of a new description, or start with a space,
a continuation of the previous line.)

Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com


> -----Original Message-----
> From: r-devel-bounces at r-project.org [mailto:r-devel-bounces at r-project.org] On Behalf
> Of Hervé Pagès
> Sent: Thursday, December 06, 2012 3:47 PM
> To: Duncan Murdoch
> Cc: christophe.genolini at u-paris10.fr; r-devel at r-project.org; Christophe Genolini
> Subject: Re: [Rd] Comments in the DESCRIPTION file
> 
> 
> 
> On 12/06/2012 03:41 PM, Hervé Pagès wrote:
> > Hi,
> >
> > Wouldn't be hard to patch read.dcf() though.
> >
> > FWIW here's the "comment aware" version of read.dcf() I've been using
> > for years:
> >
> >    .removeCommentLines <- function(infile=stdin(), outfile=stdout())
> >    {
> >      if (is.character(infile)) {
> >          infile <- file(infile, "r")
> >          on.exit(close(infile))
> >      }
> >      if (is.character(outfile)) {
> >          outfile <- file(outfile, "w")
> >          on.exit({close(infile); close(outfile)})
> >      }
> >      while (TRUE) {
> >          lines <- readLines(infile, n=25000L)
> >          if (length(lines) == 0L)
> >              return()
> >          keep_it <- substr(lines, 1L, 1L) != "#"
> >          writeLines(lines[keep_it], outfile)
> >      }
> >    }
> >
> >    read.dcf2 <- function(file, ...)
> >    {
> >      clean_file <- file.path(tempdir(), "clean.dcf")
> 
> mmh, would certainly be better to just use tempfile() here.
> 
> H.
> 
> >      .removeCommentLines(file, clean_file)
> >      on.exit(file.remove(clean_file))
> >      read.dcf(clean_file, ...)
> >    }
> >
> > Cheers,
> > H.
> >
> > On 11/07/2012 01:53 AM, Duncan Murdoch wrote:
> >> On 12-11-07 4:26 AM, Christophe Genolini wrote:
> >>> Hi all,
> >>>
> >>> Is it possible to add comments in the DESCRIPTION file?
> >>
> >>
> >> The read.dcf function is used to read the DESCRIPTION file, and it
> >> doesn't support comments.  (The current Debian control format
> >> description does appear to support comments with leading # markers, but
> >> R's read.dcf function doesn't support these.)
> >>
> >> You could probably get away with something like
> >>
> >> #: this is a comment
> >>
> >> since unrecognized fields are ignored, but I think this fact is
> >> undocumented so I would say it's safer to assume that comments are not
> >> supported.
> >>
> >> Duncan Murdoch
> >>
> >> ______________________________________________
> >> R-devel at r-project.org mailing list
> >> https://stat.ethz.ch/mailman/listinfo/r-devel
> >
> 
> --
> Hervé Pagès
> 
> Program in Computational Biology
> Division of Public Health Sciences
> Fred Hutchinson Cancer Research Center
> 1100 Fairview Ave. N, M1-B514
> P.O. Box 19024
> Seattle, WA 98109-1024
> 
> E-mail: hpages at fhcrc.org
> Phone:  (206) 667-5791
> Fax:    (206) 667-1319
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel