The high-level interface to the internal broker functionality. 

The broker agent uses an implementation of this interface.

> module QuicQuid.BrokerCore where

> import QuicQuid.Router(Address)
> import QuicQuid.Term(Term)
> import QuicQuid.Logic (Binding)

> class BrokerCore brk where
>     ask :: brk 
>         -> Term    -- ^The ask pattern
>         -> Address -- ^The asking agent address
>            -- |The matches produced.
>         -> IO [(Binding -- ^The bindings that make the answer match the ask/query
>                ,Address -- ^The address of the answer agent
>                ,Address -- ^The address of the ask agent
>                 )] 
>     answer :: brk
>            -> Term     -- ^The answer pattern
>            -> Address  -- ^The answering agent address
>            -> IO [(Binding -- ^The bindings that make the answer match the ask/query
>                   ,Address -- ^The address of the answer agent
>                   ,Address -- ^The address of the ask agent
>                   )] 

The pattern are matched according to the rules set in QuicQuid.Logic.

See also the tests in QuicQuid.BrokerTest.

TODO:
* Add "removeQuery" "removeAnswer" OR assume that query/answer is completed when the receiving channel (where results are sent) is closed.
* Fix names: newQuery | newAsk ?