// Converting method pointers into function pointers
// Often you need a function pointer for a callback function. But what, if you want to specify a method as // an callback? Converting a method pointer to a function pointer is not a trivial task; both types are // incomatible with each other. Although you have the possibility to convert like this "@TClass.SomeMethod", // this is more a hack than a solution, because it restricts the use of this method to some kind of a class // function, where you cannot access instance variables. If you fail to do so, you'll get a wonderful gpf. // But there is a better solution: run time code generation! Just allocate an executeable memory block, and // write 4 machine code instructions into it: 2 instructions loads the two pointers of the method pointer // (code & data) into the registers, one calls the method via the code pointer, and the last is just a return // Now you can use this pointer to the allocated memory as a plain funtion pointer, but in fact you are // calling a method for a specific instance of a Class.
