New library: open multi-methods

[Jean-Louis Leroy via Digitalmars-d-announce]

On Tuesday, 18 July 2017 at 02:22:15 UTC, Jay Norwood wrote:
> An excerpt statement from this wiki page is :
> "  dynamically dispatched based on the run-time (dynamic) type 
> or, in the more general case some other attribute, of more than 
> one of its arguments"
>
>
> Based on the 'some other attribute', I wonder if the library 
> could conceivably be extended to dispatch based on the User 
> Defined Attribute info
>
> https://dlang.org/spec/attribute.html
>
> @('c') string s;
> pragma(msg, __traits(getAttributes, s)); // prints tuple('c')

For example, CLOS allows you to specialize on a value (google for 
"eql specialize"). IIRC Clojure allows you to specify your own 
dispatcher.

As for specializing on D attributes, I don't think it's feasible. 
They are a purely compile-time mechanism. In your example, the 
type of "s" is "string", not "@('c') string".

J-L