Hi, But the point is that
inherits(x, "data.frame", TRUE) == 1 will not distinguish between tibbles and other classes derived from data.frame that do respect the original syntax. You cannot/want in most cases block the use of every class derived from data.frame. One would need to use a test that specifically disallows 'tibble', which is possible, but inelegant. However, maybe the main thing is that packages like tibble and magrittr are changing the syntax of R. Maybe we are reaching a point where we need to define R++, with tibbles REPLACING data frames, etc. Then it would be clear that some porting is required, and with only one syntax and behaviour in use no confusion created. Pedro. On 2017-09-26 14:47, Iñaki Úcar wrote: > 2017-09-26 13:41 GMT+02:00 Holger Hoefling <hhoef...@gmail.com>: >> Hi Thierry, >> >> You write: >> >> "If a package requires a data.frame, then it is up to the _user_ to >> provide a data.frame (and a tibble is not a data.frame). " >> >> Actually, as pointed out before, calling >> >> is.data.frame >> >> on a tibble returns TRUE. So I think that R says - yes, a tibble is a data >> frame. What would be the point of having a "is.data.frame" function, if you >> can't trust its answer? > is.data.frame is just a wrapper for inherits(x, "data.frame"). As > Daniel pointed out before, inherits(x, "data.frame", TRUE) == 1 > returns TRUE for data frames and FALSE for tibbles. > > Iñaki > > ______________________________________________ > R-package-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-package-devel -- ------------------------------------------------------------------------ Pedro J. Aphalo University Lecturer, Principal Investigator (Office 4417, Biocenter 3, Viikinkaari 1) Department of Biosciences Plant Biology P.O. Box 65 00014 University of Helsinki Finland e-mail: pedro.aph...@helsinki.fi <mailto:pedro.aph...@helsinki.fi> Tel. (mobile) +358 50 4150623 Tel. (office) +358 2941 57897 ------------------------------------------------------------------------ *Web sites and blogs* Web site (research group): http://blogs.helsinki.fi/senpep-blog/ Web site (own teaching): http://www.helsinki.fi/people/pedro.aphalo/ Web site (using R in photobiology): http://www.r4photobiology.info/ ------------------------------------------------------------------------ *Societies* UV4Plants <http://www.uv4plants.org/> (communications officer), ESP <http://www.photobiology.eu/> (member) SEB <http://www.sebiology.org/> (member), BES <http://www.britishecologicalsociety.org/> (member), SPPS <http://www.spps.fi/> (member), SMS <http://www.metsatieteellinenseura.fi/english> (member), TUG <http://tug.org/> (member), FOAS <http://www.foastat.org/> (member). ------------------------------------------------------------------------ [[alternative HTML version deleted]] ______________________________________________ R-package-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-package-devel
