You were, in effect, trying to overload the ":" operator, which is of course for defining sequences.
If you are using S4 methods, what is wrong with using the default "@" as the extraction syntax (eg. a...@name) to get at slots? See ?"@" and ?slot HTH, Marc Schwartz On Jul 9, 2010, at 7:49 AM, Renaud Gaujoux wrote: > Alright. > 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? > Thanks > > -- > 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 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel