> I share the author's conclusions: don't do that. If you find yourself slapping Mutexes and Arc/Rc all over the place it probably means that there's something messed up with the way you modeled data ownership within your program.
That's just not a very useful statement to a beginner. Rc/RefCell and Arc/Mutex have their use, for data with patterns of lifetime or mutability that cannot be derived at compile time based on program syntax - something that comes up all the time in practical programs. Of course one should seek to refactor these things out whenever possible (among other things, programs that use shared data heavily are also harder to survey wrt. correctness), but to say as a generalized statement that there's no case for this feature is just not correct. The feature is also intentionally heavy on syntax so there's no missing where you're using it.
That's just not a very useful statement to a beginner. Rc/RefCell and Arc/Mutex have their use, for data with patterns of lifetime or mutability that cannot be derived at compile time based on program syntax - something that comes up all the time in practical programs. Of course one should seek to refactor these things out whenever possible (among other things, programs that use shared data heavily are also harder to survey wrt. correctness), but to say as a generalized statement that there's no case for this feature is just not correct. The feature is also intentionally heavy on syntax so there's no missing where you're using it.