[Rd] Error: cannot set length of non-vector

[Kurt Hornik]

>>>>> Peter Dalgaard writes:

> Kurt Hornik <Kurt.Hornik at wu-wien.ac.at> writes:
>> stack info at the C level to actually see where in the code the error
>> triggers.  If I add debugging info prior to the error call, the error is
>> gone.
>> 
>> Btw, if I comment *output* redirection in tools::checkVignettes(), the
>> error is gone as well.
>> 
>> Note that this is *NOT* an error thrown by R CMD check.  The failure
>> occurs when checkVignettes() is running the code (via source()) of the
>> .R files created via Stangle(), and all the info we have about the error
>> is being passed on.

> Aha, so *that's* how to reproduce it. 

> One thing that catches my eye is that 
> tools::checkVignettes has

>     outConn <- textConnection("out", "w")
>     sink(outConn, type = "output")
>     sink(outConn, type = "message")
> ....
>            for (f in rfiles) {
>             yy <- try(source(f))

> and demo.R does extensive manipulation of an object called "out".

> Perhaps it helps to do something like local(source(f, local=TRUE))? Or
> maybe put local=TRUE in the textConnection() call.

Or maybe
	
	textConnection("out", "w", local = TRUE)

as done in similar places ...

Will try.

-k