public function isVirtual(string $propertyName): bool
    {
        $this->existsOrFail($propertyName);
        return $this->isExistingPropertyVirtual($propertyName);
    }
public function isVirtual(string $propertyName): bool
    {
        $this->existsOrFail($propertyName);
        return $this->isExistingPropertyVirtual($propertyName);
    }
public function isVirtual ( string $ propertyName ) : bool { $ this -> existsOrFail ( $ propertyName ) ; return $ this -> isExistingPropertyVirtual ( $ propertyName ) ; }
Tell whether or not a property is virtual.

@param string $propertyName
@return bool
Tell whether or not a property is virtual .