I don't know anybody who has S-plus these days, but I expect some of you might, and perhaps you won't mind telling me something.
I'm working on my presentation about R for the general audience. As I survey the suggestions from this list about that project, I find myself wondering whether S-plus benefits from R. Does S-plus syntax change like R's does. I can take code for S and run it through R, but if I took some R code to an S-plus system, would it work? Example 1. _, <-, = The old S documents I find emphasize assigment with "_". When I started with R, that was deprecated, then forbidden. "_" was not allowed in file names, now it is. It was absolutely necessary to use <-. = caused errors. Around the time of R-2.1 or so, it became possible to run R code that has = for assignments. It's not encouraged by R core team, but = is allowed. Does S+ now accept either <- or = ? For that matter, in S+ is it now forbidden to use underscore for assignment, as it is in R? Example 2. Semicolons now discouraged in R code. We used to require ; to end commands. Now the R parser is smart enough to spot line breaks and interpret them accordingly. R's been that way for as long as I can remember, but I think the ; was required in earliest R releases. I rather liked the definitive ; at the end of every command. That looks right to me, probably because of my SAS and C background. Would S+ have a panic attack? Example 3. Namespace. Does S-plus get better as R does? Years ago, I was modeling US Democrats and Republicans and I created an indicator variable called "rep". regression models would not work after that because the rep function had been blocked. It was very frustrating to me. Professor Ripley spotted the error and posed a message called "Don't use the names of R functions as variable names" http://www.mail-archive.com/r-h...@stat.math.ethz.ch/msg11585.html. After that, I was terrified that any name I used might conflict with a built in R function name. Last month, i saw a student here with a political model and he used rep as a variable in a regression model, it seemed to work just fine. I surmise that the rise in usage of namespaces in R packages accounts for that? I'm sorry if this is too OT for r-help. pj -- Paul E. Johnson Professor, Political Science 1541 Lilac Lane, Room 504 University of Kansas ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.