[Rd] dumpMethod/getMethod on methods in packages

Kasper Daniel Hansen khansen at stat.berkeley.edu
Mon Dec 14 22:42:24 CET 2009

There seems to be something wrong with dumpMethod when called on methods defined in packages (possibly with namespaces).  This may be caused by a possible bug in getMethod.

(see below for a full copy/paste without comments)


Now compare
  dumpMethod("rowSums", "ngCMatrix", file = "")  ## Nothing
  getMethod("rowSums", "ngCMatrix")  ## The method definition

Further inspection suggests that it is related to the where argument to dumpMethod, the default being where = topenv(parent.frame()) which evaluates (in this usecase) to .GlobalEnv.  I find it interesting to compare
  findMethod("rowSums", "ngCMatrix", where = .GlobalEnv)  ## Finds the method in the Matrix package
  getMethod("rowSums", "ngCMatrix", where = .GlobalEnv)  ## Does not find anything

It seems to me that getMethod is wrong when it does not find anything in the global environment.

Tested in R-2.10-patched (r50736) and R-devel (r50736)

dumpMethod works fine with example(dumpMethod) where a method gets defined in the global environment.  My usecase was trying to dump a method from a namespace I had edited with trace(..., edit = TRUE)


All 5 lines for copy and paste:

dumpMethod("rowSums", "ngCMatrix", file = "")
getMethod("rowSums", "ngCMatrix")
findMethod("rowSums", "ngCMatrix", where = .GlobalEnv)
getMethod("rowSums", "ngCMatrix", where = .GlobalEnv)

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