[Python-Dev] Caching float(0.0)
nmm1 at cus.cam.ac.uk
Tue Oct 3 20:26:29 CEST 2006
=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?= <martin at v.loewis.de> wrote:
> py> x=-0.0
> py> y=0.0
> py> x,y
Nobody is denying that SOME C90 implementations distinguish them,
but it is no part of the standard - indeed, a C90 implementation is
permitted to use ANY criterion for deciding when to display -0.0 and
0.0. C99 is ambiguous to the point of internal inconsistency, except
when __STDC_IEC_559__ is set to 1, though the intent is clear.
And my reading of Python's code is that it relies on C's handling
of such values.
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