on 9/30/2005 2:55 PM Peter Dalgaard said the following: >"Mike Prager" <[EMAIL PROTECTED]> writes: > > >>Recent R function names seem to be using CaseOfTheLetters to mark words >>rather than dots as was done previously. Is the use of dots in function >>names deprecated, or is that simply a style choice? Will function names >>with dots cause problems in future revisions? >> >> > >Well, come the S4 revolution and dots will cause trouble no more... > >The main reason dots have fallen from grace is that they cause >ambiguity in relation to S3 methods. In a nutshell: t.test is not a >transpose method for objects of class "test". Since we check S3 >methods automatically, it is problematic to keep track of things that >look like S3 methods without being so. Check out >.make_S3_methods_stop_list() (in the tools package). > My thanks to Thomas Lumley and Peter Dalgaard for their replies. Being skeptical about software revolutions, I infer that dots will be of some concern for a long time.
At the same time, I expect that having names with underscores would limit compatibility with S-PLUS. As a user, I have not encountered problems with dots, and I don't understand whether the concern is likely to apply at the user level. (I was unable to locate the function that P.D. mentioned above.) Sorry if this seems dense, but I am not particularly conversant with the internals of R nor experienced in object-oriented programming. So while I understand Peter's example showing that dots can be ambiguous, I am still at a loss as to whether that is of real practical concern at a user level; for example, in writing functions that will have limited distribution, or for functions that eventually may be incorporated into an R package. I am guessing not, but will appreciate more comments if I have that wrong.... Mike Prager ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html