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Re: p:option not required without default value

From: Innovimax SARL <innovimax@gmail.com>
Date: Fri, 29 Aug 2008 19:41:41 +0200
Message-ID: <546c6c1c0808291041k771c165bq64b7e42fdf0a81bd@mail.gmail.com>
To: "Henry S. Thompson" <ht@inf.ed.ac.uk>
Cc: "Norman Walsh" <ndw@nwalsh.com>, public-xml-processing-model-wg@w3.org

Henry,

Indeed, but option (as variable and parameter) are strings

So I fear we don't have much choice, since string(/..) = ''


Ok let's try what we really have on the table

1) We forbid to have an option that has no default and is not bound
2) We propose a default value
  2a) A default value that generate an error (which seems impossible
since string() always succeed)
  2b) The default is the empty string


If we go with 1), then we should get rid of @required, since if you
provide a default value, it cannot be required, and if there is no
@select, then it is required

If we go 2) then we stick to XSLT 1.0 and 2.0 behaviour (for good or bad)

Mohamed


On Fri, Aug 29, 2008 at 7:05 PM, Henry S. Thompson <ht@inf.ed.ac.uk> wrote:
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> Innovimax SARL writes:
>
>
>> [[
>> If an optional parameter has no select  attribute and has an empty
>> sequence constructor, and if there is no as attribute, then the
>> default value of the parameter is a zero length string.
>> ]]
>
> Yeah, but that's because its content is interpreted as a sequence
> constructor, and in XSLT 1.0 it was a content spec., which defaulted
> to the empty string, and so the above is for backwards compatibility.
> p:option is necessarily empty.  The fact that uninitialised variables
> and parameters are the empty string is a big source of bugs in XSLT,
> in my experience.
>
> ht
> - --
>       Henry S. Thompson, School of Informatics, University of Edinburgh
>                         Half-time member of W3C Team
>      10 Crichton Street, Edinburgh EH8 9AB, SCOTLAND -- (44) 131 650-4440
>                Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk
>                       URL: http://www.ltg.ed.ac.uk/~ht/
> [mail really from me _always_ has this .sig -- mail without it is forged spam]
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Received on Friday, 29 August 2008 17:42:21 GMT

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