Re: Protocol questions

[Marcus G. Daniels]

>>>>> "PJ" == Paul Johnson <address@hidden> writes:

PJ> - (int)doThis
PJ> {
PJ>   [self subclassResponsibility: @selector(doThis)]; 
PJ>   return ???????; 
PJ> }

Say, zero.
 
PJ> 2. In the Recruiter class, many methods are implemented.  Some
PJ> methods are added in typeA that are not in typeB. When I have a
PJ> typeA object, I want to use those methods, but programs won't
PJ> compile.  The compiler says the method is not in the protocol.  I
PJ> have to add these methods to the protocol to get the compiler to
PJ> work.

#import <simtools.h> // initSwarmBatch
#import <defobj/Create.h> // CreateDrop

@protocol BaseProtocol
- (void)method1;
@end

@protocol ProtocolA
- (void)method2;
@end

@protocol CompositeProtocol <BaseProtocol, ProtocolA>
@end

@interface ClassA: CreateDrop <BaseProtocol>
- (void)method1;
@end

@interface ClassB: ClassA <CompositeProtocol>
- (void)method2;
@end


@implementation ClassA
- (void)method1
{
  printf ("%s, Method 1\n", [self getName]);
}
@end

@implementation ClassB
- (void)method2
{
  printf ("%s, Method 2\n", [self getName]);
}

@end

int
main (int argc, const char **argv)
{
  initSwarmBatch (argc, argv);

  {
    id <BaseProtocol> a = [ClassA create: globalZone];
    id <CompositeProtocol> b = [ClassB create: globalZone];

    [a method1];
    [b method1];
    [b method2];
    printf ("[a conformsTo: @protocol (BaseProtocol)]: %u\n",
            (unsigned) [(id) a conformsTo: @protocol (BaseProtocol)]);
    printf ("[a conformsTo: @protocol (CompositeProtocol)]: %u\n",
            (unsigned) [(id) a conformsTo: @protocol (CompositeProtocol)]);
    printf ("[b conformsTo: @protocol (BaseProtocol)]: %u\n",
            (unsigned) [(id) b conformsTo: @protocol (BaseProtocol)]);
    printf ("[b conformsTo: @protocol (CompositeProtocol)]: %u\n",
            (unsigned) [(id) b conformsTo: @protocol (CompositeProtocol)]);

  }
  return 0;
}

/* 
Local Variables:
compile-command: "$SWARMHOME/bin/libtool-swarm --mode=link gcc 
-DAPPNAME=protocolTest -Wall -Wno-protocol -o protocolTest -g -Wno-import 
-I$SWARMHOME/include/swarm -L$SWARMHOME/lib/swarm protocolTest.m -lswarm -lobjc"
End:
*/


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