Mark Dickinson wrote:
On Sat, Aug 8, 2009 at 10:31 PM, Guido van Rossum<guido@python.org> wrote:
[...] I'd be okay with a standard API to transform a byte array into an integer and vice versa -- there you can be explicit about byte order and what to do about negative numbers. [...]
That would also be a welcome addition. It's been requested on bugs.python.org at least a couple of times[1][2], and the C code to do the conversions already exists (_PyLong_{As,From}_ByteArray in longobject.c), so it wouldn't be too much work to implement.
The main problem would be deciding exactly what the API should be and where to put it.
My suggestion would be to provide the relevant constructors as class methods on int, bytes and bytearray: bytes.from_int bytearray.from_int int.from_bytes Alternatively, the int.from_bytes classmethod could be replaced with a "to_int" instance method on bytes and bytearray. The method signatures would need to closely resemble the C API. In particular, for the conversion from int to bytes being able to state a desired size would both allow detection of cases where the value is too large as well as proper padding of the two's complement sign bit. Cheers, Nick. -- Nick Coghlan | ncoghlan@gmail.com | Brisbane, Australia ---------------------------------------------------------------