[R] "Overloading" some non-dispatched S3 methods for new classes
Carlos J. Gil Bellosta
cgb at datanalytics.com
Sat May 9 20:50:19 CEST 2009
Hello,
I am building a package that creates a new kind of object not unlike a
dataframe. However, it is not an extension of a dataframe, as the data
themselves reside elsewhere. It only contains "metadata".
I would like to be able to retrieve data from my objects such as the
number of rows, the number of columns, the colnames, etc.
I --quite naively-- thought that ncol, nrow, colnames, etc. would be
dispatched, so I would only need to create a, say, ncol.myclassname
function so as to be able to invoke "ncol" directly and transparently.
However, it is not the case. The only alternative I can think about is
to create decorated versions of ncol, nrow, etc. to avoid naming
conflicts. But I would still prefer my package users to be able to use
the undecorated function names.
Do I have a chance?
Best regards,
Carlos J. Gil Bellosta
http://www.datanalytics.com
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