On Tue, 26 Jul 2016, Maciej Izak wrote:
Hi, Finally I have a working implementation (not published yet) of Smart Pointers/ARC objects and Nullable (Nilable?) types. I think is worth to discuss a little about new "default modifier" (which is strictly related to mentioned structures). If needed I can correct details. As you know (or not) all is based on new modifier - "default" for fields. Overriding operators like "." or "^" is complicated and not obvious in Pascal world. The "default" modifier is inspired by "default" modifier for indexed properties. All of my work is (I hope so) natural for Pascal language. All FPC tests pass fine (phew!). The idea is quiet simple: "If all fails - try to use default field". Example implementation of SmartPointers and SmartObjects available at: https://github.com/maciej-izak/PascalSmartPointers (see OUTPUT on the end of each of file) Tests (very good way to see how it works. NOTE: I need to add few other tests for functions with var/const/out, "for in do" loop and for arrays and indexed properties - help with additional tests is welcome): https://github.com/maciej-izak/PascalSmartPointers/tree/master/tests The way how to obtain pointer can be a little confusing for most of Pascal programmers. Anyway nothing new for Pascal language. In Pascal we have little known @@ operator to get pointer to variable which handle pointer to procedure/function. For records with "default field" @ means "get pointer to default field" and @@ means "get pointer to record".
Very nice job indeed. I can see a lot of potential in this for ORM implementations, where IS NULL is always a difficult concept. As for ARC: I think this is a difficult topic, which should better be discussed in a separate thread. Michael. _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel
