Can someone please explain this statement?

[WetCode]

Hello am working with Unreal Engine 4 i was just wondering.
Can anyone please explain this statement for me?
const bool bMatchIsOver = MyGameState && MyGameState->bMatchIsOver;
I dont get whats happening there.
MyGameState is a class and then a bool type.

The full code looks like this.

/** Accept or reject a player attempting to join the server.
 *  Fails login if you set the ErrorMessage to a non-empty string. */
void AShooterGameMode::PreLogin(const FString& Options, 
				const FString& Address,
				const TSharedPtr<FUniqueNetId>& UniqueId,
				FString& ErrorMessage)
{
	Super::PreLogin(Options, Address, UniqueId, ErrorMessage);

	AShooterGameState* const MyGameState = Cast<AShooterGameState>(GameState);
	const bool bMatchIsOver = MyGameState && MyGameState->bMatchIsOver;
	const FString EndGameError = TEXT("Match is over!");

	ErrorMessage = bMatchIsOver ? *EndGameError : GameSession->ApproveLogin(Options);
}

Thanks for any explination.

[LB]

MyGameState is a pointer, not a class type. When pointers are used where a boolean is expected, it is the same as comparing them inequal to nullptr.

Identical code:

const bool bMatchIsOver = ((MyGameState != nullptr) && (MyGameState->bMatchIsOver != false));

[WetCode]

Thank you. so much :)

[Stewbond]

nullptr is C++11. I still haven't updated so I'll explain it in C++03 terms:

We typically use the "NULL" design pattern when working with pointers. This means we'll set the value of a pointer to 0 when it doesn't point to anything. This helps us to identify the case where it doesn't point to anything an inhibits the access to inappropriate memory.

const bool bMatchIsOver = MyGameState && MyGameState->bMatchIsOver;
Does this:

#define NULL 0
bool MatchIsOver( AShooterGameState* const MyGameState )
{
  if ( MyGameState != NULL ) // Only MyGameState actually points to something
  {
    if ( MyGameState->bMatchIsOver ) // Check the value of one of MyGameState's members
      return true;
  }
  return false;
}