Alternate string representation to the built-in str type.

• Uses C-string representation internally.
• Memory is allocated in one continuous buffer to reduce pointer-hopping.
• UTF-8 encoding.
• len returns size in bytes (not including terminating zero-byte).
• Random access (to bytes, not Unicode code points) is supported with indices and slices.

See: https://docs.python.org/3/library/stdtypes.html#str.count

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.find

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.index

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.rfind

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.rindex

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.startswith

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

See: https://docs.python.org/3/library/stdtypes.html#str.endswith

Notes:

• substring may be a cstring or Python str object.
• start and end, if provided, are byte indexes.

• Write docs (see str type docs)
• Write docstrings
• Fill out setup.py
• Allow initialization from bytes, bytearray, other cstrings, memoryview?, other?
• Read __cstring__ "dunder" on objects, if available?
• Implement iter (iterate over Unicode code points, "runes")
• Implement str methods
• Include start/end indexes as byte indexes? Calculate code points? Or just don't support?
• Implement buffer interface?
• Decide subclassing protocol