[Python-Dev] PEP: Adding data-type objects to Python
Travis E. Oliphant
oliphant.travis at ieee.org
Tue Oct 31 06:51:18 CET 2006
Greg Ewing wrote:
> Travis Oliphant wrote:
>> The 'bit' type re-intprets the size information to be in units of "bits"
>> and so implies a "bit-field" instead of another data-format.
> Hmmm, okay, but now you've got another orthogonality
> problem, because you can't distinguish between e.g.
> a 5-bit signed int field and a 5-bit unsigned int
> It might be better not to consider "bit" to be a
> type at all, and come up with another way of indicating
> that the size is in bits. Perhaps
> 'i4' # 4-byte signed int
> 'i4b' # 4-bit signed int
> 'u4' # 4-byte unsigned int
> 'u4b' # 4-bit unsigned int
I like this. Very nice. I think that's the right way to look at it.
> (Next we can have an argument about whether bit
> fields should be packed MSB-to-LSB or vice versa...:-)
I guess we need another flag / attribute to indicate that.
The other thing that needs to be discussed at some point may be a way to
indicate the floating-point format. I've basically punted on this and
just meant 'f' to mean "platform float"
Thus, you can't use the data-type object to pass information between two
platforms that don't share a common floating point representation.
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