Re: APQ

[Brian May <bam@snoopy.apana.org.au>]

>>>>> "Randy" == Randy Brukardt <randy@rrsoftware.com> writes:

    Randy> I haven't looked at the code in question, but it certainly
    Randy> is possible to have concrete operations and components on
    Randy> an abstract type (the type has be abstract - if it is
    Randy> tagged - to have abstract subprograms). We do it all the
    Randy> time in Claw and its related programs. That's the big
    Randy> difference between an abstract type and an Ada 2005
    Randy> interface (which can't have any data or concrete
    Randy> subprograms).

I tried to get it working, but couldn't:

...

   type Root_Connection_Type is abstract new Ada.Finalization.Limited_Controlled with private;

...

   procedure Connect(C : in out Root_Connection_Type) is abstract;
   procedure Connect(C : in out Root_Connection_Type; Same_As : Root_Connection_Type'Class) is abstract;

...

gcc-3.4 -c -gnata -gnatf -gnato -gnatwp -O0 comp_mysql.adb
apq.ads:126:14: abstract subprogram not allowed for type "Root_Connection_Type"
apq.ads:127:14: abstract subprogram not allowed for type "Root_Connection_Type"
apq.ads:584:09: nonabstract type has abstract subprogram "Connect"
gnatmake: "comp_mysql.adb" compilation error
make: *** [mysql1] Error 4

...

What did I do wrong? How do I create a abstract type that is derived
from Ada.Finalization.Limited_Controlled?

I thought I made it quite clear that Root_Connection_Type is abstract.

Should I try the same thing with GNAT?
-- 
Brian May <bam@snoopy.apana.org.au>