Message75498
| Author |
vstinner |
| Recipients |
fredrikj, loewis, mark.dickinson, rhettinger, terry.reedy, vstinner |
| Date |
2008年11月04日.18:15:59 |
| SpamBayes Score |
2.0208565e-06 |
| Marked as misclassified |
No |
| Message-id |
<1225822560.71.0.903135284864.issue3439@psf.upfronthosting.co.za> |
| In-reply-to |
| Content |
> It would be nicer if the OverflowError from _PyLong_NumBits
> were propagated, so that the second case raises OverflowError
> instead of giving an incorrect result
Why not, but I prefer your second proposition: return a long integer.
Attached patch implements this solution.
>>> x=1<<(2**31-1)
>>> n=x.numbits(); n, n.numbits()
(2147483648L, 32L)
>>> x<<=(2**31-1)
>>> n=x.numbits(); n, n.numbits()
(4294967295L, 32L)
>>> x<<=1
>>> n=x.numbits(); n, n.numbits()
(4294967296L, 33L) # yeah!
With my patch, there are two functions:
- _PyLong_NumBits(long)->size_t: may overflow
- long_numbits(long)->long: don't raise overflow error, but may raise
other errors like memory error |
|