At Fri, 22 Oct 2010 21:31:43 -0600, Doug Williams wrote: > Matthew, would it make more sense to have unsafe-vector-ref (and related > functions) be the more general function and unsafe-vector*-ref be the one > that doesn't work on chaperoned vectors? That is just swap the definitions. > That way user code that is already using unsafe-vector-ref (etc) will > continue to work. > > As it stands, existing code that has unsafe-vector-ref (etc) will often > still work (in the sense of not getting any error or crashing), but just > gives the wrong results. For example, if you run science-test.ss from the > examples directory in the science collection, there are no errors. But, some > of the answers are wrong - for example the very first one, the gamma > function. [In other cases, like the FFT routines, there are either run-time > errors or crashes.] > > Anyway, if it isn't too late, I think swapping the definitions would make > more sense and be safer.
I've gone back and forth. I agree that it would be safer, but `vector-ref' is safer still, and I think of the job of `unsafe-X' as providing the lowest possible overhead over `X'. It seems nicer to me to have `*' mean "somewhere in between" rather than "even faster". Then again, it seems bad that `vector?' (plus index bounds) isn't enough to guard `unsafe-vector-ref'. Overall, at this point in the release cycle, I'm inclined to leave things where they are (i.e., it may be too late). But let's hear more opinions from those who use `unsafe-vector-ref' and unsafe-vector*-ref'. _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
