search for: vector_sexprec

There seems to be a latent flaw in the definition of struct SEXPREC in Rinternals.h, which likely doesn't cause problems now, but could if the relative sizes of data types changes. The SEXPREC structure contains a union that includes a primsxp, symsxp, etc, but not a vecsxp. However, in allocVector in memory.c, zero-length vectors are allocated using allocSExpNonCons, which appears to

Dear all, Internally, the attribute list appears to be implemented as an generic list vector with a names attributes (i.e., the attribute slot in the object's SEXPREC structure would point toward a VECTOR_SEXPREC representing a generic vector). > attributes(c(a=1)) $names [1] "a" > typeof(attributes(c(a=1))) [1] "list" From R, it appears as if the named list had itself an named attributes list and so on .... until no end > attributes(attributes(c(a=1))) $names [1] "n...