[R] a problem sourcing a file using chdir=TRUE

[Prof Brian Ripley]

There was a pre-existing bug.  ?source in 2.0.1 says

     file: a connection or a character string giving the name of the
           file or URL to read from.

yet it contained

     if (chdir && (path <- dirname(file)) != ".") {

You cannot reasonably run dirname() on a connection or a URL, and it 
throws an error in those cases.

We need a more elaborate detection mechanism, and some re-ordering of the 
code.


On Mon, 16 May 2005, Luca Scrucca wrote:

> Dear R-users,
>
> I used to give commands such as:
>
>> source(file="~/path/to/file.R", chdir=TRUE)
>
> but with the latest v. 2.1.0 it does not seem to work anymore.
> I tried to figure out what it was going on and it seems that the string
> for which
>> class(file)
> [1] "character"
> is changed to
>> class(file)
> [1] "file"       "connection"
> when the connection is open by
> file <- file(file, "r", encoding = encoding)
>
> But this force the following if statement
> if (chdir && is.character(file) && (path <- dirname(file)) != ".")
>   { owd <- getwd()
>     on.exit(setwd(owd))
>     setwd(path)
>   }
> to be FALSE and then non changing of current directory is done.
> Is this the desired behavior or some bug fix is required?
>
> Luca
>
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> | Dr. Luca Scrucca                                                      |
> | Dipartimento di Economia, Finanza e Statistica                        |
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-- 
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