Re: [Bug-apl] Miscellaneous minor fixes

[Dr . Jürgen Sauermann]

Hi Alexey, I applied most of your patches, thanks for submitting them. I have left the preferences file as is because changing it could come as a surprise to users that are happily using the current default. I also changed the rlim_t comparison warnings in a different way. Please complain if that doesn't work. SVN 1179. BR, Jürgen On 7/4/19 5:52 PM, Alexey Dokuchaev wrote: On 7/4/19, Dr. Jürgen Sauermann <mail@jürgen-sauermann.de> wrote: Regarding signed vs. unsigned, the question is not so much if the chosen type can hold the value but the number of comparisons needed to compute if a value fits into a range (where the vast majority of cases the range starts at 0). A signed X falls into range [0, N] iff: X ≥ 0 and X < N An unsigned X falls into range [0, N] iff: X < N Understood. It should not be too hard to fix, just make sure that your desired types do not conflict with system types like rlim_t, then either use a compatible type or employ a typecast as a last resort (typecasts are evil and should be avoided). This fired back badly (with milllions of warnings) when I replaced Simple_string<X> with std::string<X> which uses unsigned for the length. Been these, done that. :-) Usually, the safest approach when handling sizes is to use size_t type (which is unsigned, just as you prefer) and only reluctantly fallback to ssize_t if you need/must to handle negative sizes for some reason in the same variable (e.g. for error handling). Reluctantly because it is generally a bad idea to convey errors by abusing the data type itself. Unfortunately, in many traditional languages there is no support for algebraic data types to handle these situations in a correct, type-safe way. ./danfe