R devel - Jun 2012 - Convert "\" to "/"?

Hello, All:


	  I have for years copied an address like "C:\Program 
Files\R\R-2.15.0\library\MASS\scripts" from Windows Explorer into R, 
then manually replaced "\" with "/".  I have a function to
automate this
added to the development version of "sos".  However, it generates a 
warning in "R CMD check" ("parse error:  unexpected input").
I have so
far not found a way to eliminate the warning without wrapping examples 
in "\dontrun" or making the examples hard to understand;  neither of 
these alternatives are acceptable.


	  The following is my current solution:


back2ForwardSlash <- function(nmax=1, what=character(), sep='\n',
...){
   x2 <- scan(what=what, nmax=nmax, sep=sep, ...)
   x. <- gsub('\\', '/', x2, fixed = TRUE)
}
(x <- back2ForwardSlash())
c:\Users\
all.equal(x, 'c:/Users/')
# TRUE
x2. <- back2ForwardSlash(2)
c:\u\a b\n o
d:/pqr/
all.equal(x2., c('c:/u/a b/n o', 'd:/pqr/'))
# TRUE


QUESTION:  Might anyone have a better solution and / or simple, clear 
examples that do not generate a warning in "R CMD check"?


NOTE:  In case you want to try this development version of "sos" 
including this function, it is available via "svn checkout 
svn://svn.r-forge.r-project.org/svnroot/rsitesearch/" or 
install.packages('sos', repos =
"http://R-Forge.R-project.org").


	  Thanks,
	  Spencer


p.s.  Prof. Ripley provided a way to do this on R-help several years 
ago.  Unfortunately, I've been unable to find his solution.

One work around is to comment out the lines that `scan` reads.

    (x <- back2ForwardSlash())
    #c:\Users\
    all.equal(x, '#c:/Users/')

Or, you could pass a text arg through the dots

    (x <- back2ForwardSlash(text="c:\\\users"))
    all.equal(x, 'c:/users')

HTH,
Garrett

On Sat, Jun 9, 2012 at 8:40 PM, Spencer Graves
<spencer.graves at prodsyse.com> wrote:
> Hello, All:
>
>
> ? ? ? ? ?I have for years copied an address like "C:\Program
> Files\R\R-2.15.0\library\MASS\scripts" from Windows Explorer into R,
then
> manually replaced "\" with "/". ?I have a function to
automate this added to
> the development version of "sos". ?However, it generates a
warning in "R CMD
> check" ("parse error: ?unexpected input"). ?I have so far
not found a way to
> eliminate the warning without wrapping examples in "\dontrun" or
making the
> examples hard to understand; ?neither of these alternatives are acceptable.
>
>
> ? ? ? ? ?The following is my current solution:
>
>
> back2ForwardSlash <- function(nmax=1, what=character(),
sep='\n', ...){
> ?x2 <- scan(what=what, nmax=nmax, sep=sep, ...)
> ?x. <- gsub('\\', '/', x2, fixed = TRUE)
> }
> (x <- back2ForwardSlash())
> c:\Users\
> all.equal(x, 'c:/Users/')
> # TRUE
> x2. <- back2ForwardSlash(2)
> c:\u\a b\n o
> d:/pqr/
> all.equal(x2., c('c:/u/a b/n o', 'd:/pqr/'))
> # TRUE
>
>
> QUESTION: ?Might anyone have a better solution and / or simple, clear
> examples that do not generate a warning in "R CMD check"?
>
>
> NOTE: ?In case you want to try this development version of "sos"
including
> this function, it is available via "svn checkout
> svn://svn.r-forge.r-project.org/svnroot/rsitesearch/" or
> install.packages('sos', repos =
"http://R-Forge.R-project.org").
>
>
> ? ? ? ? ?Thanks,
> ? ? ? ? ?Spencer
>
>
> p.s. ?Prof. Ripley provided a way to do this on R-help several years ago.
> ?Unfortunately, I've been unable to find his solution.
>
> ______________________________________________
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> https://stat.ethz.ch/mailman/listinfo/r-devel