Re: bit strings - anyone working on them?

At 10:36 AM 23/04/2003 -0400, Tom Lane wrote:

> > Cast(8 as bit(10)) => '0001000000'
> > Cast(8 as bit(4)) => '0001'
>
>That part we could do, I think, if you are willing to abandon the
>assumption that the result of casting int to bit(n) and then to bit(m)
>should agree with the result of casting int directly to bit(m).

I'm not sure I follow the implication; in fact I would hope that:
    Cast(B'0001' as bit(10))

would yield '0001000000'.



> > B'1' # Cast(1 as bit(32)) => '00000000000000000000000000000000'
>
>Eh?  What is the # operator supposed to be doing here?

It's the XOR operator.  Current implementation has:
    Cast(B'1' as bit(32)) XOR Cast(1 as bit(32))
giving    10000000000000000000000000000001

Another thing I have forgotten to mention is that there are no 
text<->varbit conversions.


>Perhaps these
>operators should only exist for varbit, or should demand inputs already
>the same length for bit.

That seems like a good idea. I'd prefer to make these changes for varbit only.





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