Support programmatically-generated tag attributes

[quickfur]

I have no idea if this is actually already supported because the docs are very incomplete, but I'm having a frustrating time trying to figure out how to generate a <meter> tag whose list of attributes is generated by embedded D code. (It's not just the values of the attributes that are unknown, but whether or not certain attributes even appear in the tag in the first place. The former is easy; the latter I'm having a really hard time with.) Is this even remotely possible, or do I have to generate the tag from D code and inject it into the output?

I found something about &attributes online in the Jade Template spec, but it seems Diet doesn't support this syntax. If such a thing is not yet supported by Diet, it would be very nice if this feature could be added. Perhaps something along the lines of:

html
    body
        - auto attrs = [ "min": "0", "max": "100" ];
        - if (hasOptimal) attrs["optimal"] = optimalValue;
        meter(value=#{value})&attributes(attrs)

Or if this feature already exists in some form, please at least mention it in the docs.

[s-ludwig]

There is currently just one way implemented to have attributes omitted at runtime, which is having the type of argument given as a string or char array and setting the value to null.

But I didn't know about the &attributes syntax until now, and it unfortunately conflicts with the i18n syntax foo& This is translated text, so something else will have to be used for Diet.

meter(min=0, max=100, optimal=hasOptimal ? optimalValue.to!string : null)

[quickfur]

OK, using null strings to suppress attributes should suffice for now. I can work with that.

I'm not too concerned about the exact syntax for transforming an AA into an attribute list, and honestly I think the &attributes syntax is rather ugly. But having some way of doing this would be very nice. Thanks!

[quickfur]

P.S. Also, is the null string thing documented anywhere? I don't remember seeing a reference to it. It would be nice to at least mention it somewhere so that people like me can find the information. :)