[Python-Dev] RFC: PEP 460: Add bytes % args and bytes.format(args) to Python 3.5

[Victor Stinner]

2014/1/8 Ethan Furman <ethan at stoneleaf.us>:
>> Therefore you shouldn't accept integers. It does not make sense to
>> format 4 as b'4'.
>
> Agreed.  I would have that it would result in b'\x04'.

The PEP proposes b'%c' % 4 => b'\x04.

Antoine gave me a good argument against supporting b'%s' % int: how
would int subclasses be handled? int has no __bytes__() nor
__bformat__() method. bytes(int) returns a string of null bytes.

I'm maybe simpler to only support %s format with bytes-like objects
(bytes, bytearray, memoryview).

Victor