SE-0307: Allow interchangeable use of CGFloat and Double types

[tkremenek (Ted Kremenek)]

@DevAndArtist

Hello Ted and the core team, I as a daily Swift user would wish that the language would explicitly make implicit bridging conversions visible. The Apple frameworks (even Foundation) seem to lack this feature and it‘s very hard to discover if you missed or simply didn‘t follow the language evolution. I for myself spent a few hours recently researching how to use UIFont in SwiftUI. I didn‘t know that I could just implicitly bridge UIFont to CTFont. That said I would appreciate if type bridging and implicit conversions were somehow discoverable like type inheritance or protocol conformances.

It’s a good suggestion. I’ll look into it, but if folks are interested they can spin up conversations here on the forums to talk about how such a think could be implemented from he compiler’s side. Ultimately any feature built into an editor would need the compiler’s knowledge to power such an experience. For example, a SourceKit API to provides this information. Etc.