Hi Gabriel, here is a simple package for reproducing the problem. https://github.com/Jiefei-Wang/testPkg
Best, Jiefei On Thu, Oct 8, 2020 at 5:04 AM Gabriel Becker <gabembec...@gmail.com> wrote: > Jiefei, > > Where does the code for your altrep class live? > > Thanks, > ~G > > On Wed, Oct 7, 2020 at 4:25 AM Jiefei Wang <szwj...@gmail.com> wrote: > >> Hi all, >> >> The coercion function defined for the ALTREP object will not be called by >> R >> when an assignment operation implicitly introduces coercion for a large >> ALTREP object. >> >> For example, If I create a vector of length 10, the ALTREP coercion >> function seems to work fine. >> ``` >> > x <- 1:10 >> > y <- wrap_altrep(x) >> > .Internal(inspect(y)) >> @0x000000001f9271c0 13 INTSXP g0c0 [REF(2)] I am altrep >> > y[1] <- 1.0 >> Duplicating object >> Coercing object >> > .Internal(inspect(y)) >> @0x000000001f927c08 14 REALSXP g0c0 [REF(1)] I am altrep >> ``` >> >> However, if I create a vector of length 1024, R will give me a normal >> real-type vector >> ``` >> > x <- 1:1024 >> > y <- wrap_altrep(x) >> > .Internal(inspect(y)) >> @0x000000001f8ddb20 13 INTSXP g0c0 [REF(2)] I am altrep >> > y[1] <- 1.0 >> > .Internal(inspect(y)) >> @0x000000001f0d72a0 14 REALSXP g0c7 [REF(1)] (len=1024, tl=0) >> 1,2,3,4,5,... >> ``` >> >> Note that the duplicate function is also called for the first example. It >> seems like R completely ignores my ALTREP functions in the second example. >> I feel this might be designed on purpose, but I do not understand the >> reason behind it. Is there any reason why we are not consistent here? Here >> is my session info >> >> sessionInfo() >> R Under development (unstable) (2020-09-03 r79126) >> Platform: x86_64-w64-mingw32/x64 (64-bit) >> Running under: Windows 10 x64 (build 18362) >> >> Best, >> Jiefei >> >> [[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
