== Quote from Simen kjaeraas (simen.kja...@gmail.com)'s article > Pluto <pl...@planets.not> wrote: > > == Quote from Simen kjaeraas (simen.kja...@gmail.com)'s article > >> Pluto <pl...@planets.not> wrote: > >> > This part has always bothered me. Could somebody please explain to me > >> the > >> > rationale behind limiting functions to one usable error code? > >> Well, traditionally it was done because testing for 0/non-0 is a simple > >> and fast operation. > > So speed it is. Was <1 really slower back then? > Likely not. But the assembly is easier: > jnz <label>; vs cmp EAX 0; jg <label>; That might explain things.
> >> Also, boolean logic can be thought of as simple maths, > >> as AND is multiplication and OR is addition. This only makes sense if > >> false == 0. > > false < 1, is what I would expect. > > It even makes it more symmetrical. > How? > Let's start out with a false value f of -1. Now AND it with itself > (f * f), and you get 1, which is true. This does not seem correct. Not knowing anything about assembler(and ignoring history), this seems sensible to me: f is an integral, not a boolean. For it to work like a boolean it needs a cast, implicit or explicit: cast(bool); >0?true:false if(returnsErrorCodes()); implicit cast from return value to bool f*f; integral operation and should return the multiplication f&f; bitwise operation and should return bitwise AND cast(bool) f & cast(bool) f; bitwise operation on booleans ~~ :Pluto
