setGeneric() gives "must supply skeleton" when checking package

r-devel,

In a development version of the CRAN package metrumrg, I write ...

require(reshape)
setGeneric('cast')
setOldClass(c('keyed','data.frame'))
setMethod('cast','keyed', function ...)

The result is satisfactory when sourcing the code directly, but when
checking the package (which has 'reshape' as a dependency in the
DESCRIPTION file) I get the following:

"Error in setGeneric("cast") : must supply a function skeleton for
???cast???, explicitly or via an existing function."

The help for setGeneric() seems to suggest that no function skeleton is
needed  when creating a generic for a function defined in some other
package.  I found one or two previous related posts, but no obvious
resolution.

Comments appreciated,

Tim Bergsma, PhD

	[[alternative HTML version deleted]]

On 02/02/2013 02:34 PM, Tim Bergsma wrote:

r-devel,

In a development version of the CRAN package metrumrg, I write ...

require(reshape)
setGeneric('cast')
setOldClass(c('keyed','data.frame'))
setMethod('cast','keyed', function ...)

The result is satisfactory when sourcing the code directly, but when
checking the package (which has 'reshape' as a dependency in the
DESCRIPTION file) I get the following:

"Error in setGeneric("cast") : must supply a function skeleton for
???cast???, explicitly or via an existing function."

You haven't mentioned your DESCRIPTION or NAMEPSACE file, but the right thing to
do is

DESCRIPTION:

Depends: reshape

NAMESPACE:

importFrom(reshape, cast)

R/somefile.R:

setGeneric("cast")

Perhaps your current setGeneric is being performed inside the namespace when
cast is not yet available (e.g., because it has not been imported)?

Martin Morgan

The help for setGeneric() seems to suggest that no function skeleton is
needed  when creating a generic for a function defined in some other
package.  I found one or two previous related posts, but no obvious
resolution.

Comments appreciated,

Tim Bergsma, PhD

    [[alternative HTML version deleted]]