I'm unable to reproduce this with R 3.6.1. Which version are you using? Is this a fresh session?
On Mon, Jul 15, 2019 at 3:25 AM Ghiggi Gionata <gionata.ghi...@epfl.ch> wrote: > > Hi all ! > > I noticed a strange behaviour of the function `class<-` when a class-specific > '[[.' method is defined. > > Here below a reproducible example : > > > #-------------------------------------------------------------------. > > counttt <- 0 > > `[[.MYCLASS` = function(x, ...) { > counttt <<- counttt + 1 > # browser() > x = NextMethod() > return(x) > } > > df <- as.data.frame(matrix(1:20, nrow=5)) > class(df) <- c("MYCLASS","data.frame") > counttt > > # The same occurs when using structure(, class=) or attr(,"class")<- > df <- as.data.frame(matrix(1:20, nrow=5)) > df <- structure(df, class=c("MYCLASS","data.frame")) > attr(df, "class") <- c("MYCLASS","data.frame") > > #-------------------------------------------------------------------. > > Why in this example `class<-` is calling `[[.MYCLASS` 9 times ? > > Is there a way to avoid `class<-` to call `[[.MYCLASS` ? > > > Thank you in advance for your help and suggestions. > > Gionata > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel -- Michael Lawrence Scientist, Bioinformatics and Computational Biology Genentech, A Member of the Roche Group Office +1 (650) 225-7760 micha...@gene.com Join Genentech on LinkedIn | Twitter | Facebook | Instagram | YouTube ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel