You define a goal using the macro ILCGOALn. The definition consists of three parts:

For example, the following goals merely print something, but they are valid goal definitions:

ILCGOAL0(Print){
    cout << "Print: executing a goal without parameters\n";
    return 0;
}
ILCGOAL1(PrintX, IlcInt, x){
    cout << "PrintX: executing a goal with one parameter\n";
    cout << x << endl;
    return 0;
}
ILCGOAL2(PrintXY, IlcInt, x, IlcFloat, y){
    cout << "PrintXY: executing a goal with two parameters\n";
    cout << x << endl;
    cout << y << endl;
    return 0;
}

The definition of a goal defines a function for calling it. In that sense, a goal call is a function call. For example, the following are valid calls of the goals just defined.

Print(solver);
PrintX(solver, 2);
PrintXY(solver, 1, 2.);

The goal calling function can be declared in a header file. Its signature has the same name and parameters as the goal, and it returns a pointer to an object of the type IlcGoal.

For example, the following declarations are valid declarations of these same goals:

IlcGoalI Print(IloSolver solver);
IlcGoalI PrintX(IloSolver solver, IlcInt x);
IlcGoalI PrintXY(IloSolver solver, IlcInt x, IlcFloat y);

You can also define a goal using subgoals. The following goal has three subgoals:

ILCGOAL0(PrintAll){
   IloSolver solver=getSolver();
   return IlcAnd(Print(solver), PrintX(solver, 2), PrintXY(solver, 1, 2.));
}

The execution of the goal PrintAll produces the following output:

Print: executing a goal without parameters
PrintX: executing a goal with one parameter
2
PrintXY: executing a goal with two parameters
1
2