observer_ptr

[HFriberg]

Upon reading your document, https://github.com/tvaneerd/isocpp/blob/master/observer_ptr.md, I found one missing argument which is the main reason I am looking into observer_ptr, namely the technique called strong typing (see, e.g., the blogpost at https://www.fluentcpp.com/2016/12/05/named-constructors/). In my case, I have two variables with vastly different meaning (like double radius and double diameter in blogpost), but with the same pointer type (say double *radius_handle and double *diameter_handle for the sake of example, though you may come up with something better). To distinguish them (from a function overloading perspective) I plan on wrapping them in distinct class types as described in the blogpost (e.g., a class called RadiusHandle to hold double* radius_handle as member). Rather than just boxing/unboxing at every relevant function as the blogpost suggests, I had the idea to simply use observer_ptr as the base class for my strong types, and just use those strong types directly as they are via the observer_ptr functionality. No need to box and unbox. In fact, in this scenario, only owners needs to see the raw pointers (whose types can't be distinguished), and all observers can just use the strong types.

If you want, you can use this argument in favor of standardizing observer_ptr. Otherwise, just close this documentation request.