Pumpmanager updates #1
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ps2
commented
Nov 20, 2018
ps2
commented
- PumpManagerUI vending HUDViews
- Updates to PumpManagerStatus model
- Multiple observers of PumpManager status updates
Travis use xcode10
Update to Swift 4.2
Return correct units per hour for netBasalUnitsPerHour for boluses
…bject, and cleanup NS upload
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This is an interesting approach to tackling the problem of aggregating weak references; I wasn't aware of NSHashTable.weakObjects().
However, we can implement this generically without requiring NSObject inheritance (or relying on Obj-C classes at all). Note that it's impossible to retain complete type safety when working with class-constrained protocol types as the generic parameter, as protocols don't conform to themselves*, which is the issue we're fighting here. I wrote about experiencing this problem a few months ago but didn't get much solid feedback.
That said, here's a sketch of a pure-Swift WeakSet type. It still suffers the limitation of not being able to enforce that its generic parameter is a class or class-constrained protocol at compile-time, but I think it's an improvement over the Obj-C-reliant variant.
* There are a couple exceptions here: @objc-annotated protocols self-conform, and there's an open PR in apple/swift to do the same for Error in light of recent discussion regarding the addition of Result to the stdlib. Adding a way to self-conform a protocol in Swift has come up but doesn't have concrete plans AFAIK.
