Using dynamic_cast in c++

Question

I have 4 classes in c++ . Animal is the super class were Snake and Tiger inherit from Animal but also inherit from Dangerous Animal . I have implemented a function to check if Snake or tiger is an instance of DangerousAnimal . However I am finding problems in implemting it in c++

my code is :

bool Vet::examine (Animal *someAnimal){

        if(DangerousAnimal* s = dynamic_cast<DangerousAnimal*>(Animal)){
            return false;
        }else{
            return true;
        }
    }

The error is

dillu24@dillu24-VirtualBox:~/Desktop/OOP/Lab1$ g++ -std=c++11 -oAnimalWellBeingLauncher AnimalWellBeingLauncher.cpp q1.cpp
q1.cpp: In member function ‘bool Vet::examine(Animal*)’:
q1.cpp:122:64: error: expected primary-expression before ‘)’ token
   if(DangerousAnimal* s = dynamic_cast<DangerousAnimal*>(Animal)){

The code, the code, where is the code! Please provide a [MCVE](http://stackoverflow.com/help/mcve): Minimal (OK) Complete (!!) Verifiable (!!) Example. Your example is neither complete nor verifiable, and therefore you will need multiple round-trips to get your code to compile. — Matthieu M., Oct 29 '16 at 18:47

score 2 · Answer 1 · answered Oct 29 '16 at 15:42

2

The syntax of dynamic_cast is dynamic_cast<TargetType>(variable), so you have to write dynamic_cast<DangerousAnimal*>(someAnimal).

answered Oct 29 '16 at 15:42

Hugal31

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Lloge it is saying source type is not polymorphic – Dylan Galea Oct 29 '16 at 15:47
@DylanGalea - no, the error message is saying that `Animal` isn't the right kind of argument to `dynamic_cast`; it should be `someAnimal`, as this answer says. – Pete Becker Oct 29 '16 at 15:52
2

@PeteBecker: Dylan is reporting the _next_ error, which is due to the classes being defined incorrectly. – Lightness Races in Orbit Oct 29 '16 at 15:56
@LightnessRacesinOrbit - that may well be, but it's not in the question, nor is it at all clear from the code. And, of course, a comment to an answer is not an appropriate place to bring up a new issue. – Pete Becker Oct 29 '16 at 16:17
@PeteBecker: I concur. But that is what happened, so your comment response was (at best) misplaced. – Lightness Races in Orbit Oct 29 '16 at 16:27

Using dynamic_cast in c++

1 Answers1