Re: EXPath Binary module: bin:unpack-integer()

On 03/10/2013 12:35, Christian Grün wrote:
>> The usual convention in F&O is that "data arguments" allow an empty sequence, and "control arguments" don't. Data arguments are those that can be seen as supplying the data on which the function operates, control arguments as those that qualify what the function does. Of course the distinction is highly subjective.
> Interesting, thanks. When having a look at the bin:or function...
>
>    bin:or($a as xs:base64Binary, $b as xs:base64Binary) as xs:base64Binary
>
> ...I would assume that $a is a data argument and $b is a control
> argument. Would you agree?
In this case, both are obviously data, even more so that for these 
functions the arguments can be swapped with no change to the result. 
They also have the constraint that they have to be the same 
octet-length. If we allow xs:base64Binary?, then they either both must 
be the empty sequence, or both be a similar length xs:base64Binary.

I'd prefer to let things stand unless someone has a real use case.

John

-- 
*John Lumley* MA PhD CEng FIEE
john@saxonica.com <mailto:john@saxonica.com>
on behalf of Saxonica Ltd