Push comes to shove in this case:

  <attribute name="whatever" type="color" style="color" value="black" />

Here we have an attribute that is styleable using CSS, which may specify a 
value in a number of ways:  named color, #format, rgb(), hsv(), etc.  It's 
pretty clear (to me at least) that the fallback/default specified in `value` 
should be in that same space.  I should _not_ have to say `value="0"` to 
specify a default color of black.

Therefore, I propose, at least for attributes that have a `style` property, the 
`value` property is assigned to the attribute using the specified type's 
`accept` method.

On 2010-08-11, at 11:44, P T Withington wrote:

> Here's an important question that needs answering, before we can really go 
> anywhere with this:
> 
> If I define a new type, say `trilean`, that is stored as 0, 1, or 2, but is 
> meant to represent a tri-state yes/no/maybe button in a form, when I write:
> 
>  <attribute name="again" type="trilean" value="???" />
> 
> What is the expectation about the `value` field?
> 
> Currently, for all the built-in presentation types, (except for color), 
> `value` is interpreted as the corresponding Javascript type, but maybe this 
> is just luck because the Javascript type and the LZX type look similar enough 
> no one noticed.  E.g.,  I say:
> 
>  <attribute name="ok" type="boolean" value="false" />
> 
> I use the Javascript value `false`, not the representation `"false"` (which 
> is how a boolean would be stored in a dataset).
> 
> If we extend that model, for my trilean, I would have to write:
> 
>  <attribute name="again" type="trilean" value="2" />
> 
> which is not really helpful.  I would have to remember wether `2` corresponds 
> to "yes", "no", or "maybe".  I would much rather write:
> 
>  <attribute name="again" type="trilean" value="maybe" />
> 
> Is this what people expect?  I'm not sure how we could reconcile the current 
> built-in types with this new distinction.  It makes me think that we need a 
> new property of attribute that is the "representation type"?
> 
>  <attribute name="again" type="trilean" ???="maybe" />
> 
> What's a good name for that?
> 
> [that leaves open the issue of how I write Javascript code to manipulate 
> `this.again` -- there I need to know the corresponding values.  Probably I 
> want to be able to say:
> 
>  if (this.again == lz.trilean.yes) ...
> 
> or something.]
> 
> 


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