22:00 - The fact that Swift already supports the complexity of dynamically-sized types for all these abstraction reasons actually means we're also well set up to support them for other reasons. For example, people have been talking about how to support fixed-size arrays in Swift for awhile; if we add that feature, I think we could relatively easily go further and support non-constant bounds, and we wouldn't have to restrict where they appear the way that e.g. C99 does with VLAs.