[R-pkg-devel] debian-clang error with class

[Christian Martin Hennig]

Hi there,

I have an ERROR in my fpc package on debian-clang that I currently 
cannot reproduce due to the fact that rhub is apparently affected by a 
bug on that platform that doesn't allow me to install Bioconductor 
packages. The description is "--- failure: the condition has length > 1 
---". I have googled for this and have found that there are a lot of 
packages that have such an error on debian-clang only. In all cases this 
seems to be associated with lines that compare a class of some object 
with a string such as

if (class(xxx)!="try-error"), if (class(m)=="matrix"), if (class(y) %in% 
c("onething,"anotherthing")) etc.

(The fpc package apparently achieved this with a "try-error" check.)

Now on my machine (which isn't debian-clang) the class of xxx is a 
harmless thing, either "try-error" or another simple string (in the 
example that caused the error it is actually "matrix"), so it's not 
clear to me what's wrong with this on debian-clang. However, looking at 
all these other cases in other packages, I'm pretty sure that the error 
comes from comparing class(something) with a string.

Can anybody shed some light on this? What goes wrong with 
class(xxx)!="try-error" and the like on debian-clang that works elsewhere?

Thanks,

Christian


-- 
Christian Hennig
Dipartimento di Scienze Statistiche "Paolo Fortunati",
Universita di Bologna, phone +39 05120 98163
christian.hennig using unibo.it