For Debug, use DWARF and don't analyze for faster Edit-Build-Test cycle.
Switch from OBJC_EXPORT (in objc-api.h) to FOUNDATION_EXPORT (in Foundation.h)
Extract helper methods in NSInvocation category
Transform NSInvocation else-if chain into Chain of Responsibility
Move non-core files into Helpers
Change initializer return types to instancetype
Add comment to explicitly identify Chain of Responsibility
Replace macro'd implementations with spelled out ones, but use @(value) literals