Changes

Summary

1. tuned signature;
2. clarified signature;
3. tuned signature;
4. tuned output;
5. removed junk (amending 236e43c8bb5b);
6. tuned;
7. tuned output;
8. tuned performance: much faster low-level operation;
9. clarified signature: more general operation Bytes.read_slice;
10. clarified signature: more explicit types;
11. clarified signature: more explicit types;
12. clarified signature: more explicit types; tuned output;