couldn't find function "setClass"

John Chambers writes:

Prof Brian Ripley wrote:

On Tue, 16 Sep 2003, John Chambers wrote:

Jeff Gentry wrote:

Hello ...

With a new checkout of R-devel (last update was 2003-09-11) we are having
a problem (it seems to be happening to all of us here on a few different
machines) where during install/check/etc when the 'save image' happens (in
packages using 'save image'):

** save image
Error: couldn't find function "setClass"
Execution halted

This is for all packages that are using classes.

Is anyone else having this problem?

With packages that do NOT have a namespace but DO have saved images,
yes. (!)

The problem seems to be that the current version of INSTALL doesn't end
up with library(methods) in this branch (related to --vanilla ?).  One

It's not related to --vanilla, which does not change the packages loaded.
See Kurt's comment for what I believe is the true reason.

workaround seem to be to change INSTALL (or scripts/INSTALL.in) as
follows:

522c522
<       code_cmd="eval cat \"${code_file}\""
---

      code_cmd="eval echo \"library(methods)\"; cat \"${code_file}\""

to explicitly attach the library.  This may in fact be the right fix,
but I'm confused as to why this is happening now.

I don't think so: methods is currently optional and Doug's fix seems to be
to be the right one.

That (apparently) the problem arises in such a special situation is
confusing for users.  At least for me, it's ONLY in the combination of
saved image and no namespace.

That the user does not need a require(methods) when testing the code
directly but does (sometimes) when the source code is in package
source is not a feature.  If we can avoid this complexity, that would
encourage package developers.

Unfortunately, it is not necessarily true that require(methods) is not
needed when testing: site admins or "users" might have changed the
default packages from the system default.

Otoh, once we use --vanilla for the save image creation, it seems that
this eliminates all (reasonable) possibilities for changing the default
packages (or am I missing something?).  So we could use the system
default rather than just base here.

-k