[Rcpp-devel] package .onLoad multiple modules

[baptiste auguie]

Thanks, that is helpful. I think I have nailed down the problem.

I defined a wrapper at R level that used a C++ function from a module
named "cd",

circular_dichroism_spectrum <- function( ... ){

 [...] # some argument processing

  res <- cd$circular_dichroism_spectrum(...) # calling the C++ function

 return(res)
}

Now, with loadRcppModules(), no "cd" module is created, as far as I
can tell, and invoking circular_dichroism_spectrum() is calling the
C++ function directly; a segfault results because some of the
arguments differ between the C++ function and its R wrapper.

I see two options:

- choose a different name for the R and C++ functions

- manage some kind of namespace masking the C++ function from the
top-level, like cd$ did before. Is there a way to do this in the
loadRcppModules() approach?

Best regards,

baptiste


On 30 May 2011 11:11, Dirk Eddelbuettel <edd at debian.org> wrote:
>
> On 30 May 2011 at 10:29, baptiste auguie wrote:
> | Hi,
> |
> | On 30 May 2011 04:28, Dirk Eddelbuettel <edd at debian.org> wrote:
> | >
> | > On 29 May 2011 at 18:56, baptiste auguie wrote:
> | > | Dear list,
> | > |
> | > | [Disclaimer: I am not very familiar with Rcpp/C++, and probably
> | > | haven't followed all the relevant discussions on this list.]
> | > |
> | > | I'm trying to tidy up two packages on r-forge [*] before submitting
> | > | them to CRAN. In "cda/zzz.r", I have the following code,
> | > |
> | > | NAMESPACE <- environment()
> | > | cda <- new( "Module" )
> | > | cdatests <- new( "Module" )
> | > | cd <- new( "Module" )
> | > | linear <- new( "Module" )
> | > | array <- new( "Module" )
> | > |
> | > | .onLoad <- function(libname, pkgname){
> | > |   unlockBinding( "cda" , NAMESPACE )
> | > |   unlockBinding( "cdatests" , NAMESPACE )
> | > |   unlockBinding( "cd" , NAMESPACE )
> | > |   unlockBinding( "linear" , NAMESPACE )
> | > |   assign( "cda", Module( "cda" ), NAMESPACE )
> | > |   assign( "cdatests", Module( "cdatests" ), NAMESPACE )
> | > |   assign( "cd", Module( "cd" ), NAMESPACE )
> | > |   assign( "linear", Module( "linear" ), NAMESPACE )
> | > |   lockBinding( "cda", NAMESPACE )
> | > |   lockBinding( "cdatests", NAMESPACE )
> | > |   lockBinding( "cd", NAMESPACE )
> | > |   lockBinding( "linear", NAMESPACE )
> | > |
> | > |   unlockBinding( "array" , NAMESPACE )
> | > |   assign( "array", Module( "array" ), NAMESPACE )
> | > |   lockBinding( "array", NAMESPACE )
> | > |
> | > | }
> | > |
> | > | It seems to work, but is there something I can/should do to make this
> | > | a wee cleaner?
> | >
> | > Have another look at the Rcpp-modules vignette, and/or the third set of
> | > slides ("Advanced Rcpp") from our class in April -- you no longer need the
> | > unlockBinding / lockBinding business as Romain internalized that. The
> | > skeleton-generated packages now just do this in zzz.R:
> | >
> | >  .onLoad <- function(pkgname, libname){
> | >      loadRcppModules()
> | >  }
> | >
> | > using a 'RcppModules: cda, cdatests, cd, linear, array' declaration in
> | > DESCRIPTION.
> |
> | Strange, this does not seem to work for me.
> |
> | If I use the following zzz.r, (with RcppModules listed in DESCRIPTION)
> |
> | .onLoad <- function(libname, pkgname){
> |    loadRcppModules()
> | }
> |
> | I get a segfault whenever I use a c++ function,
> |
> |  *** caught segfault ***
> | address 0x0, cause 'memory not mapped'
> |
> | Traceback:
> |  1: .External(list(name = "InternalFunction_invoke", address =
> | <pointer: 0x101407f30>,     dll = list(name = "Rcpp", path =
> | "/Library/Frameworks/R.framework/Versions/2.13/Resources/library/Rcpp/libs/x86_64/Rcpp.so",
> |         dynamicLookup = TRUE, handle = <pointer: 0x101441030>,
> | info = <pointer: 0x1002b3ed0>), numParameters = -1L),     <pointer:
> | 0x103011050>, ...)
> |  2: circular_dichroism_spectrum(clust, gold, n = 1.33, N = 36, progress = FALSE)
> |  3: onecluster()
> |
> | Is there another step I'm missing?
>
> My first instinct is to check the unitTest, so look at what is different in
> test run from
>
>   inst/unitTests/runit.Module.client.package.R
>
> using
>
>   inst/unitTests/testRcppModule/
>
> That should still work on your platform and you should be able to go from there.
>
> Dirk
>
> --
> Gauss once played himself in a zero-sum game and won $50.
>                      -- #11 at http://www.gaussfacts.com
>