[Rd] Defining a method that behaves like '$'?

Renaud Gaujoux renaud at mancala.cbio.uct.ac.za
Fri Jul 9 14:49:39 CEST 2010

Maybe the symbol I chose was not appropriate. I tried ':' to be able to 
do 'a:name' with 'a' a S4 object.
I get the following error:
Error in genericForPrimitive(f) :
   methods may not be defined for primitive function ":" in this version 
of R

Does there exist any symbol that would be suitable for the job?

Renaud Gaujoux
Computational Biology - University of Cape Town
South Africa

On 09/07/2010 14:29, Duncan Murdoch wrote:
> On 09/07/2010 8:18 AM, Renaud Gaujoux wrote:
>> Hi,
>> is there a way to define a method say '$$' that would behave like '$' 
>> and allow calls like 'a$$name'?
> No, the parser handles a fixed syntax, and that expression is not 
> legal.  You could do it with
> a %$$% name
> using the infix operator syntax.  (I think the description in the R 
> Language Definition suggests this is not legal, since $$ is not a 
> valid name, but it does currently work and that's unlikely to change.)
> Duncan Murdoch



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