Re: c++ reflection (was (no subject))

  Not sure anyone is still following this thread. I've just spent 10mn 
to improve the interface so that the Member macro doesn't have such a 
rigid number of arguments:

I think the following code is quite easily expandable, and it now looks 
quite much like what Jarkko wanted: easy to have lots of parameters, no 
code generation tool, no precompilation pass.

    class Foo
    {
    public:
         Foo() {}
         virtual ~Foo() {}

    private:
         DefineClass(Foo);

         Member(int, test, Default(0); Description("Some int") );
         Member(char *, mName, Default("foo"); Description("Some static
    text"); Serialized());

         Member(int*, mBuffer, Default(NULL), Description("Some ptr to
    nowhere"); Serialized());

         Member(int, foo);

         Member(int, foo2, Description("this one has a desc, unlike foo"));
         Member(int, foo3, Default(0xDead));

         EndClass();
    };

Updated code is still in the same place: 
http://tfpsly.free.fr/Files/Reflection.cpp



On 24/06/10 00:24, Sylvain G. Vignaud wrote:
> Actually you can get something quite similar if you're not too regarding on mixing metaprogramming and macros. The result looks like:
>
> 	class Foo
> 	{
> 	public:
> 		Foo() {}
> 		virtual ~Foo() {}
>
> 	private:
> 		DefineClass(Foo);
> 	
> 		Member(int, test, 0);
> 		Member(char *, mName, "foo");
> 	
> 		Member(int*, mBuffer, NULL);
> 	
> 		EndClass(Foo);
> 	};
>
> 	Foo foo;
> 	foo.InitializeMembersToDefaultValue();
>
> 	const Foo::ClassDescription&desc = Foo::GetClassDescription();
>
> 	printf("type: %s\n", desc.name());
> 	printf("size: %d\n", desc.size());
>
> 	for( int i=0; i<Foo::NbrMembers; ++i )
> 	{
> 		const member_t&member = desc.m_Members[i];
> 		printf("  %s: offset %d  size %d  type %s\n",
> 			member.name, member.offset,
> 			member.type->size(), member.type->name());
> 	}
>
> And it seems the "Member" macro doesn't prevent Intellisense and the likes to know about members :)
> Also it could be expended to take more parameters, like a flag to decide which members are serialized, a text description...
>
> Quick proof of concept with full code - hacked using Jon Watte's Reflexion.cpp as a basis:
> http://tfpsly.free.fr/Files/Reflection.cpp
>
>
>
> From: Jarkko Lempiainen [Profoundic]<jarkko
>
>> [...] But it would be nicer to have something like:
>> struct my_struct
>> {
>>    int a {serialized, editable, desc("Car velocity"), color(0x123456)};
>>    int b {serialized, editable, call(foobar())};
>>    int c, d, e {serialized};
>>    int f; // non-reflected variable
>> };
>>
>> Cheers, Jarkko
>>
>>
>>
>> From: sweng-gamedev-bounces<at>  lists.midnightryder.com
>> [mailto:sweng-gamedev-bounces<at>  lists.midnightryder.com] On Behalf Of Jon Watte
>> Sent: Thursday, June 17, 2010 1:13 AM
>> Am 17.06.2010 00:12, schrieb Jon Watte:
>>> Mail formatting still all messed up :-(
>>>
>>> Anyway, the example you had (PFC_MONO()) doesn't actually add all the
>>> annotations you want for editing and serialization in addition to the
>>> general reflection information.
>>>
>>> You can get rid of the ellipsis requirement by doing something like:
>>>
>>> #define MEMBERS(Type, x) \
>>>    typedef mytype Type; \
>>>    inline static Member *GetMembers() { \
>>>      static Member<mytype>[] members = { \
>>>        x \
>>>      }; \
>>>      return x; \
>>>    }
>>>
>>> #define MEMBER(x, desc) Member<mytype>(&mytype::x, #x, desc),
>>>
>>> Use it like so:
>>>
>>> struct MyStruct {
>>>    int x;
>>>    float b;
>>>    MEMBERS(MyStruct,
>>>      MEMBER(x, "Some integer value")
>>>      MEMBER(b, "The amount of float-ness"))
>>> };
>>>
>>> Note that the comma lives in the MEMBER() macro, and the members are
>>> just listed without comma within the MEMBERS() macro. The MEMBER()
>>> macro should take the union of all information you need about the
>>> member (editor information, networking, etc).
>>>
>>> Sincerely,
>>>
>>> jw
>
> _______________________________________________
> Sweng-Gamedev mailing list
> [email protected]
> http://lists.midnightryder.com/listinfo.cgi/sweng-gamedev-midnightryder.com
>

_______________________________________________
Sweng-Gamedev mailing list
[email protected]
http://lists.midnightryder.com/listinfo.cgi/sweng-gamedev-midnightryder.com