[Python-Dev] Weekly Python Bug/Patch Summary
mwh at python.net
Thu Feb 19 14:17:44 EST 2004
"Tim Peters" <tim.one at comcast.net> writes:
> [Michael Hudson]
>>>> Would it make (more) sense to implement rich comparisons for floats?
>>> Not much.
>> But a little bit? It might at least make the results closer to what
>> the underlying C compiler does (modulo bugs in same, of course).
> The intended behavior of NaNs is covered precisely by standards. Moving
> Python's nonsense behavior closer to the platform C's nonsense behavior
> doesn't scream "useful" to me.
As you say below, it helps with gcc (which more-or-less claims C99
support of late, so no great surprise).
> But I don't object to it either, if someone can't think of something
> better to do with their time <wink>.
Heh. See the patch I just attached to the report :-)
> At least gcc users would get something much closer to what the
> standard intends (although their Python wouldn't be portable in
> these respects). OTOH, by pure accident, NaN==NaN *happens* to
> return the intended False today under Windows Python, and if that's
> changed, via rich comparison, to return True (which MSVC returns for
> the C expression NaN==NaN), then we've also managed to break
> currently-working code on Windows.
Is MSVC 7 any different here? I did try to poke around
msdn.microsoft.com and found:
This version of Visual C++ is not conformant with the C99
which (a) was in a section about the library specifically and (b)
doesn't answer the question. Oh, hang on:
suggests (very much) that this *has* changed. But "someone" should
check (I can't).
(I certainly wasn't proposing this change for release23-maint).
> 754 really isn't friendly to half-assed support.
Indeed. But I think were the underlying compiler implements C99
semantics, it's unfriendly of Python to hide them.
Ignoring the rules in the FAQ: 1" slice in spleen and prevention
of immediate medical care.
-- Mark C. Langston, asr
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