LockIsolated value access with a timeout

[rhr-gc]

I see that LockIsolated uses an NSRecursiveLock as the synchronization mechanism. I also notice that to get a value stored by LockIsolated the pattern is to use the value computed property. This calls into the lock() function of NSRecursiveLock.

NSLocking provides a method lock(before:) that allows client code to supply a timeout parameter. I think this would be a useful addition to LockIsolated. In my specific case, there is a low-priority piece of data that would be nice to have when sending along a network request, but not necessary - and ultimately not worth blocking the network request. Being able to request a LockIsolated value with a timeout would be valuable.

[mbrandonw]

Hi @rhr-gc, this is definitely an interesting idea, but in the long run we plan on deprecating LockIsolated in favor of the new Mutex type in Swift 6. So we don't think we should be adding new features to this type. Luckily the type is simple enough that you could always maintain your own version of it.