deftype makes no extender?

[alux]

Hello,

shouldnt the type x be listed a extender of xx here? Or why not?

Thanks, alux

(defprotocol xx "example" (xxx [x] "some x'es"))

(deftype x [] xx (xxx [x] :xxx))

(extenders xx)

=> nil

[Meikel Brandmeyer]

Hi,

On 3 Sep., 12:49, alux <alu...@googlemail.com> wrote:

> shouldnt the type x be listed a extender of xx here? Or why not?

No. It shows up if you actually use extend to the extend the protocol
to the type.

Sincerely
Meikel

[alux]

Yes, thats what I see.
I just dont think this is very sensible.

Thank you Meikel!

Greetings, alux

[Stuart Halloway]

Let's back up: what are you trying to do with 'extenders'?

Stu

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[alux]

Hello Stuart, sorry to answer so late, got holidays, happily.

I tried to use the function extenders to list the implementations, so
to say, of the protocol.
That was playing around, not a use case taken from reality. If I try
to make a use case up, hm, I may need it in the development
environment, to find functions to ponder their use.

Regards, alux

[Stuart Halloway]

The first rule of open dispatch club is "you never get a complete list of club members." :-) This is also true for e.g. Java interfaces: there is no API call for "reflectively show me all implementers of this interface."

The IDE/tools use case is a real one, but it will need to be solved in the same way IDEs currently find all implementers of an interface: the information is in the environment, not in the core of the language.

Stu

[alux]

Hi Stu,

I like your "open dispatch club" ;-)

Yes, after some thinking this is rather clear - every single something
had to be scanned whether it implements a protocol; ehm, and rescanned
when a new protocol is defined.

Well, I drop that request ;-)

Thank you for the illumination,

alux