R devel - Dec 2011 - makeNamespace and rdyncall

Dear R Core Team,

I have a question related to the programming interface for namespace object
creation at run-time.

This is something that I need in the rdyncall package:
During the dynamic linkage binding of a shared C library, an R namespace object
is created
that gets populated with call wrappers, symbolic constants and type information
objects.

For example,
> dynport(SDL) # create namespace, populated with wrappers to SDL library 
> search()     # gives a "package:SDL" populated with all kinds of
wrappers to the C functions, etc..
[1] ".GlobalEnv"        "package:SDL"  

I was trying various alternatives to get package-behaviour implemented in
transparent manner for the end-user.

The current version uses real namespace environments with all sorts of
advantages such as support for
search(), detach() and '::'.

Namespace object have certain conventions for fields, and there is currently no
public interface available in 'base' for setting up such objects;
The function "makeNamespace" in src/library/base/namespace.R is
defined as local function to "loadNamespace".
So I go about this problem by 'copying' the code.

Recently, R-2.14 introduced a new mandatory field 'lazyData' which mades
rdyncall broken.
(By re-synchronizing with 'makeNamespace' it has been fixed in 0.7.4.)

Would it be possible and feasible to make namespace-related management functions
such as makeNamespace and sealNamespace
available as an public accessible interface? Or at least accessible via
':::' ?

I would also appreciate any hint/idea for alternative ways to implement the
above described behaviour.

Here is the link to the code used for creation of dynamic C binding namespaces:
http://dyncall.org/svn/dyncall/trunk/bindings/R/rdyncall/R/dynport.R

best wishes,
- Daniel

This is also something I'd appreciate for the devtools package.
Hadley

On Fri, Dec 16, 2011 at 7:36 AM, Daniel Adler <dadler at
uni-goettingen.de> wrote:
> Dear R Core Team,
>
> I have a question related to the programming interface for namespace object
creation at run-time.
>
> This is something that I need in the rdyncall package:
> During the dynamic linkage binding of a shared C library, an R namespace
object is created
> that gets populated with call wrappers, symbolic constants and type
information objects.
>
> For example,
>
>> dynport(SDL) # create namespace, populated with wrappers to SDL library
>> search() ? ? # gives a "package:SDL" populated with all kinds
of wrappers to the C functions, etc..
> [1] ".GlobalEnv" ? ? ? ?"package:SDL"
>
> I was trying various alternatives to get package-behaviour implemented in
transparent manner for the end-user.
>
> The current version uses real namespace environments with all sorts of
advantages such as support for
> search(), detach() and '::'.
>
> Namespace object have certain conventions for fields, and there is
currently no
> public interface available in 'base' for setting up such objects;
> The function "makeNamespace" in src/library/base/namespace.R is
defined as local function to "loadNamespace".
> So I go about this problem by 'copying' the code.
>
> Recently, R-2.14 introduced a new mandatory field 'lazyData' which
mades rdyncall broken.
> (By re-synchronizing with 'makeNamespace' it has been fixed in
0.7.4.)
>
> Would it be possible and feasible to make namespace-related management
functions such as makeNamespace and sealNamespace
> available as an public accessible interface? Or at least accessible via
':::' ?
>
> I would also appreciate any hint/idea for alternative ways to implement the
above described behaviour.
>
> Here is the link to the code used for creation of dynamic C binding
namespaces: http://dyncall.org/svn/dyncall/trunk/bindings/R/rdyncall/R/dynport.R
>
> best wishes,
> - Daniel
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel


-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/