Create 0184-improved-pointers.md

[tayloraswift]

Adds a proposal for improving Swift’s unsafe pointer API.

Swift’s pointer types are an important interface for low-level memory manipulation, but the current API design is not very consistent, complete, or convenient. Many memory methods demand a capacity: or count: argument, forcing the user to manually track the size of the memory block, even though most of the time this is either unnecessary, or redundant as buffer pointers track this information natively. In some places, poor naming choices and overengineered function signatures compromise memory safety by leading users to believe that they have allocated or freed memory when in fact, they have not.

This proposal seeks to improve the Swift pointer API by ironing out naming inconsistencies, adding sensible default argument values, adding missing methods, and reducing excessive verbosity, offering a more convenient, more sensible, and less bug-prone API.

Swift-evolution thread: Pitch: Improved Swift pointers, Pitch: More Improved Swift pointers