Re: Priorities of unionised patterns

You're asking as if we had a choice. But the semantics have been well defined
since 1999, so why raise the question now?

And the approach you are proposing is very paternalistic. Disallowing things
because the user might not understand what they are doing is not generally a
good design principle, especially when it breaks orthogonality. (Treating the
separate parts of a union pattern differently was already a serious breach of
orthogonality, but that's a different question.)

Michael Kay
Saxonica

On 9 Apr 2013, at 12:37, Ihe Onwuka wrote:

> Given that the sub parts of a unionized pattern retain their individual
> priorities
>
> <xsl:template match="A|B[*] ......
>
> What should be the semantic if you were to now specify a priority
attribute.
> The instinctive reaction would be they should all get the same priority but
> there not a case for saying that it should not be allowed.
>
> The rationale would be to highlight that the subparts may have had
> different priorities in the first place so making their priorities
> homogenous might actually be the source of what would be a hard to find
bug.