- From: <hme@informatik.uni-rostock.de>
- Date: Thu, 17 Jan 2002 16:57:19 +0100
- To: Jerome Simeon <simeon@research.bell-labs.com>
- Cc: www-ql@w3.org
Hello Jerome,
You (Jerome Simeon) wrote:
> Holger,
>
> The XQuery static typing handles dynamic element names fine. The trick
> is to realize that wildcard names are part of the type system and can be
> used to type such an operation.
>
> For instance:
>
> element title { "Lord of the Rings" }
> has type
> element title { xs:string }
>
> and:
>
> element { if $language = "french" then "titre" else "title" } { "LoTR" }
> has type
> element * { xs:string }
>
> where the * is a wildcard that stands for all possible QNames.
>
> So you can statically type this expression without problem, you just get
> a less precise type.
A type that stands for all possible types precisely. If the evaluation
generates a value that is not a QName at all than a dynamic type
exception happens? Or did XQuery not check the type during the
evaluation phase in this circumstance?
Is that really static typing anymore?
> You can see more details about the typing for element constructors in
> section 4.4 of the XQuery formal semantics (June working draft).
You are right, I'll have a closer look at that draft.
Regards
Holger
--
Holger Meyer, Uni of Rostock, Dpt. of CS, DB Research Group
hm at GUUG.de, http://www.informatik.uni-rostock.de/~hme/
Received on Thursday, 17 January 2002 10:57:23 UTC