Peter Vreman wrote: >> On Saturday 14 October 2006 15:55, Marc Weustink wrote: >>> Hi, >>> >>> if I define 2 types like: >>> >>> type >>> MyA = type string; >>> MyB = type string; >>> >>> are MyA and MyB considered as the same type ? >> No, you are explicitly marking them as a new type. This is a very cool >> feature >> of Pascal you wont find in many other languages. >> >> (For instance, you could use it to create a new integer-type for little- >> and >> big-endian numbers, ensuring that you _never_ directly assign a >> little-endian >> number to a big-endian one, or vice versa) > > For the compiler the types are not equal anymore, but they are still > compatible for implicit type conversion. This has mainly impact on > overload choosing and parameter passing. Normal assignments using ':=' are > not affected because of the still available implicit type conversion.
I came to this when I wanted to do operator overloading on them. The compiler complained that you cannot overload for equal types. So I wanted first to know if it are equal types or not. Next question: Should operator overloading be possible on such types ? Marc _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
