[R] About the method dispatch mechanism

Sharpie chuck at sharpsteen.net
Tue Dec 1 07:42:40 CET 2009



Peng Yu wrote:
> 
> I see the follow explanation in help(cbind). I don't understand what
> the dispatch mechanism is. Could you point me what document or
> reference I should read?
> 
>      The method dispatching is _not_ done via 'UseMethod()', but by
>      C-internal dispatching. Therefore, there is no need for, e.g.,
>      'rbind.default'.
> 

The reference to "C-internal dispatching" and the fact that rbind() and
cbind() hand off execution to .Internal() are all strong indicators that
method dispatching and execution for these functions are handled in the C
source code that makes up the guts of R.  I don't know of any documentation
that describes what happens to rbind() and cbind() at this level.

If you really want to know what happens, the applicable source code is
bind.c which can be located after downloading and unpacking the R source
code at:

  R-2.x.y/src/main/bind.c

Or online at:

  https://svn.r-project.org/R/branches/R/src/main/bind.c
-- 
View this message in context: http://n4.nabble.com/About-the-method-dispatch-mechanism-tp931912p931939.html
Sent from the R help mailing list archive at Nabble.com.




More information about the R-help mailing list