[tmql-wg] Proposed requirements: Operations on primitive types

[Dmitry]

From: "Lars Marius Garshol"
To: <tmql-wg@isotopicmaps.org>
Sent: Tuesday, July 22, 2003 7:52 AM
Subject: Re: [tmql-wg] Proposed requirements: Operations on primitive types

> | I really like the way it is done in XPath 2.0.
> |
> | 1) for literals it is possible to use constructors:
xs:date('1993-08-01')
> | 2) dynamic type converters such as:  number(price), date(birthdate)
> | 3) 'instance of' operator which allows to verify that operand is of
specific
> | type
>
> Hmmm. This is rather different from what XPath 1.0 did, and which I
> always liked very much. Could you say something about why you think
> this is superior? (I see the benefit of 3, of course.)

Explicit constructors/converters + ability to specify data type during TM
authoring can help to increase query engine efficiency.

BTW, in this case efficient querying can be done even without TMCL if TM
author  uses "typed" data.
...with something like this: urn:date('2003-07-23')

Dmitry