Terry Reedy wrote:
"Tim Peters" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
All Python behavior in the presence of a NaN, infinity, or signed zero
is a platform-dependent accident.
The particular issue here is not platform dependence as such but
within-platform usage dependence, as in the same code giving radically
different answers in a standard interactive console window and an idle
window, or when you run it the first time (from xx.py) versus subsequent
times (from xx.pyc) until you edit the file again. (I verified this on 2.2,
but MSpencer claimed to have tested on 2.4). Having the value of an
expression such as '100 < 1e1000' flip back and forth between True and
False from run to run *is* distressing for some people ;-).
I know that this has come up before as 'wont fix' bug, but it might be
better to have invalid floats like 1e1000, etc, not compile and raise an
exception (at least on Windows) instead of breaking the reasonable
expectation that unmarshal(marshal(codeob)) == codeob. That would force
people (at least on Windows) to do something more more within-platform
deterministic.
If marshal could reliably detect a NaN, then of course unmarshal
should reliably reproduce the NaN -- provided the platform on which
it's unpacked supports NaNs
Windows seems to support +- INF just fine, doing arithmetic and comparisons
'correctly'. So it seems that detection or reproduction is the problem.
Terry J. Reedy
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/python-python-dev%40m.gmane.org
I can write the Windows-dependent detect code if that is what is wanted.
I just want to know what the consensus is on the "should." If we cause
exceptions, should they be one encode or decode or both? If not, do we
replicate all NaNs, Infs of both signs, Indeterminates?....
--Scott David Daniels
[EMAIL PROTECTED]
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
