On Tue, 31 May 2011, Thomas Friedrichsmeier wrote:
On Tuesday 31 May 2011, [email protected] wrote:
Also note at the beginning of of th help file:
Utility functions to access and replace the non-exported functions
in a name space, for use in developing packages with name spaces.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is intended only as a developer convenience, not as something to
be used in production code. It is quite deliberate the name spaces are
intended to be read-only once created. This allows the compiler to
make assumptions about functions/constants defined in a name space.
For now the compiler only uses this infomation for the base packages,
but that could change in the future.
Could you elaborate a bit? In RKWard, we do make use of assignInNamespace(),
mostly in order to insert hooks into functions where there are none by
default. For example, in order to get correct interleaving of output generated
by system() commands, and R output, we insert two calls for synchronization
inside base::system() and base::system2(). As another example, we add some
code into utils::select.list() to provide our own UI if graphics=TRUE. In
total, currently, we have around a dozen calls to assignInNamespace(), for
which I do not see any workable alternative.
None of these changes the function formals, environment, or type of return
value. All of this is done only once, at the start of the session. Should I be
worried that it will still interact badly with the compiler?
Yes you should. Changing things in other people's packages is not a
safe thing to do.
Best,
luke
Regards
Thomas
--
Luke Tierney
Statistics and Actuarial Science
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa Phone: 319-335-3386
Department of Statistics and Fax: 319-335-3017
Actuarial Science
241 Schaeffer Hall email: [email protected]
Iowa City, IA 52242 WWW: http://www.stat.uiowa.edu
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