[R] building packages using S4 methods

[Marsland, John]

I have been building a package around a sequence of S4 classes which I have
coded in separate *.R files in the "./R" subdirectory of the package.
The package builds without error, but when I load it in R I get:

Error in reconcilePropertiesAndPrototype(name, slots, prototype,
superClasses) :
	Class "xxxx" extends an undefined class ("yyyyyy"

I guess R is trying to source the *.R files in the wrong order? Since both
classes are defined in the package and work fine at the command prompt. 
Is it just that this has not been an issue before owing to R's lazy
evaluation?
Is there anything I can do about this... maybe by putting something in the
"./install.R"?

Regards,

John Marsland

using: R v1.7.1 on Windows NT 4


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