help with automatic code generation

[JoshforRefugee]

heard that we can do automatic code generation using macros, but not
sure how can I pursue this. Here is my problem.

In my env, I have class A,B and C. All of them has constructors, and
few common methods, like reset, and execute.

now my env(main) class actually is where I am creating this objects.
in .h
A myA;
B myB;
C myC;

and later I am calling methods in my .C file
myA.reset();
myB.reset();
myC.reset();
myA.execute();
.....
myC.execute();

now let say if I add Class D, I have to modify my env.h and env.C. And
I am trying to prevent that.
one way i was thinking of doing this, is to write macros:
so I can do:
REGISTER_OBJECT("A","myA");
REGISTER_RESET("A","myA",reset);
REGISTER_EXECUTE("A", "myA", execute)
.............

May be using macros might be one way to do this. I am really confuse
how I can I write this macros. Please guide me.

Thank you,

[Ole Nielsby]

JoshforRefugee <an*****@yahoo.comwrote:

heard that we can do automatic code generation using macros, but not
sure how can I pursue this. Here is my problem.

In my env, I have class A,B and C. All of them has constructors, and
few common methods, like reset, and execute.

Don't bother with macros for things that can be done with simple
OO techniques. Your classes should probably derive from a base
class that declares the common methods as virtuals.

[JoshforRefugee]

problem is I own env class, and my group owns other classes. and I
don't want to be bother by creating class and registering its
function, every time someone adds new class or wants to create new
object for same class.

how can I do this?

[Grizlyk]

JoshforRefugee wrote:

>
how can I do this?

What do you want - new names for single class? Or what?

--
Maksim A Polyanin

[JoshforRefugee]

just an interface for users so that they can register their classes
with my "main/env" class.

What I am doing, is collecting all classes out there, written by users
and constructing objects for them, and calling their methods (reset,
run). Users derived their class from base object class. Right now,
when someone adds new class, I have to open up "main/env" class and
create object for new class, and call common methods (reset, run) for
that new object.

My goal is to not manually touch "main/evn" class, everytime someone
creates new class. Let have some hooks that users can use so that they
can create these class and reset/run methods will be call for
them.

[=?iso-8859-1?q?Erik_Wikstr=F6m?=]

On Jan 31, 7:16 pm, "JoshforRefugee" <[e-mail]:

just an interface for users so that they can register their classes
with my "main/env" class.

What I am doing, is collecting all classes out there, written by users
and constructing objects for them, and calling their methods (reset,
run). Users derived their class from base object class. Right now,
when someone adds new class, I have to open up "main/env" class and
create object for new class, and call common methods (reset, run) for
that new object.

My goal is to not manually touch "main/evn" class, everytime someone
creates new class. Let have some hooks that users can use so that they
can create these class and reset/run methods will be call for
them.

Can't you do something like this:

class env {
std::vector<Base*classes;
public:
void register(Base& b) {
classes.push_back(&b);
}
void resetAll() {
for (size_t i = 0; i < classes.size(); ++i)
classes[i]->reset();
}
};

I kind of assume here that you'll only have one instance of env (a
singleton comes to mind) but even if you don't you might be able to
use this approach. The idea is that the new classes registers
themselves with your env instance either when constructed or soon
after.

--
Erik Wikström

[JoshforRefugee]

that is good help. Thank you Erik.
that will take care of registering functions for new classes.
How about creating object for this class. Can I automate that?

so now in my top class, where I am doing

class top {
env myEnv;
A myA;
B myB;
C myC; //can I automate this creating
public:
void run() {
myEnv.resetAll();
myEnv.execute();
}

};

something like this in my classes will be very useful:

DECLARE (A, "myA");
DECLARE (A, "myAA");
class A {
.......

}

DECLARE(B, "myB");
class B {
....
}

so basically user has control how many objects to create.