On Thursday, 18 October 2018 at 23:47:56 UTC, Timon Gehr wrote:
I'm pretty sure you will have to allow operations on shared local variables. Otherwise, how are you ever going to use a shared(C)? You can't even call a shared method on it because it involves reading the reference.
Because you can't really "share" C (e.g. by value). You share a C*, or, rather a shared(C)*. The pointer itself, which you own, isn't shared at all, and shouldn't be: it's your own reference to shared data. You can read and write that pointer all you want. What you must not be able to do is read and write *c.
Although, when it's a global?.. I'm not sure. We can have the compiler always generate a by-reference access, i.e. make that part of the language spec. Because full-on read of C.sizeof can't be statically proven thread-safe generically anyway (that's why generated copying and assignment don't make any sense for `shared`).
