Hi, Thanks for the note. How would explain the following snippet taken from `formals` doc page (the code comment is also from that doc) ?
## formals returns NULL for primitive functions. Use it in combination with ## args for this case. is.primitive(`+`) formals(`+`) formals(args(`+`)) Le sam. 6 oct. 2018 à 13:42, Rui Barradas <ruipbarra...@sapo.pt> a écrit : > Hello, > > I believe that this is maybe not a *feature* but at least expected > behaviour. > > The call formals(args(`[`)) breaks down to > > > > args(`[`) > NULL > > formals(NULL) > NULL > Warning message: > In formals(fun) : argument is not a function > > > Hope this helps, > > Rui Barradas > > > Às 18:26 de 06/10/2018, Laurent Gautier escreveu: > > Hi, > > > > A short code example showing the warning might the only thing needed > here: > > > > ``` > >> formals(args(`[`)) > > NULL > > > > *Warning message:In formals(fun) : argument is not a function* > >> is.function(`[`) > > [1] TRUE > >> is.primitive(`[`) > > [1] TRUE > > ``` > > > > Now with an other primitive: > > > > ``` > >> formals(args(`sum`)) > > $... > > > > > > $na.rm > > [1] FALSE > > > >> is.function(`sum`) > > [1] TRUE > >> is.primitive(`sum`) > > [1] TRUE > >> class(`[`) > > [1] "function" > > ``` > > > > Is this a feature ? > > > > > > Laurent > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-devel@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-devel > > > [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel