Achieving those goals required some innovative library interface techniques. Those techniques are equally useful for anyone designing classes. Core language C-compatible subset Classes, members, virtual, etc. Language is perhaps the first specifically designed to support Library Design. Any style of programming.
Interfaces remain compatible with higher- level structures.
Basic structures suffice for interlibrary communication. Innovative interface design using the full power of the language. Requirements Convenience for simple uses. Latin-1, EUC, Unicode, etc. The iostreams library has years of history Must generalize and internationalize without breaking existing programs.