User Defined Attributes

[Jacob Carlborg]

On 2012-11-06 19:36, Walter Bright wrote:

> You're right, there is none. That's why using type names as attributes
> is more scalable and robust.

Then why allow it? Actually the more I think about it the more I think 
you're right in that it's better to use a proper symbol or type name. 
But I still don't like the syntax.

> I understand your desire to have attributes be implicitly declared, but
> I think that implicit declarations have historically been seductive, and
> much later were realized to be a mistake. This pattern has happened over
> and over :-)

Actually I don't. I was just trying to stay close to your 
implementation. This is one of my proposals, from a one the threads you 
linked to:

http://www.digitalmars.com/d/archives/digitalmars/D/Proposal_user_defined_attributes_161624.html#N161742

In that proposal you have to clearly define an attribute, like:

attribute class serializable { }

attribute class name
{
     string fieldName;
}

@serializable class FooBar
{
     @name("foo") int bar;
}

"serializable" and "name" would be symbols you can import have the same 
name look up rules any other symbol.

-- 
/Jacob Carlborg