On 11/27/2011 9:33 AM, Irmen de Jong wrote:
Hi,
A bytearray is pickled (using max protocol) as follows:
pickletools.dis(pickle.dumps(bytearray([255]*10),2))
0: \x80 PROTO 2
2: c GLOBAL '__builtin__ bytearray'
25: q BINPUT 0
27: X BINUNICODE u'\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff'
52: q BINPUT 1
54: U SHORT_BINSTRING 'latin-1'
63: q BINPUT 2
65: \x86 TUPLE2
66: q BINPUT 3
68: R REDUCE
69: q BINPUT 4
71: . STOP
bytearray("\xff"*10).__reduce__()
(<type 'bytearray'>, (u'\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff', 'latin-1'),
None)
Is there a particular reason it is encoded so inefficiently? Most notably, the
actual
*bytes* in the bytearray are represented by an UTF-8 string. This needs to be
transformed into a unicode string and then encoded back into bytes, when
unpickled. The
thing being a bytearray, I would expect it to be pickled as such: a sequence of
bytes.
And then possibly converted back to bytearray using the constructor that takes
the bytes
directly (BINSTRING/BINBYTES pickle opcodes).
The above occurs both on Python 2.x and 3.x.
Any ideas? Candidate for a patch?
Possibly. The two developers listed as particularly interested in pickle
are 'alexandre.vassalotti,pitrou' (antoine), so if you do open a tracker
issue, add them as nosy.
Take a look at http://www.python.org/dev/peps/pep-3154/
by Antoine Pitrou or forwary your message to him.
--
Terry Jan Reedy
--
http://mail.python.org/mailman/listinfo/python-list
