As a first remark, I wouldn’t call it ObjectArray if it is a map and not an array. Anyway, you can insert objects this way: ObjectArray myMap; myMap.insert(std::make_pair(0, std::unique_ptr<Class1>(new Class1()))); Or this way: ObjectArray myMap; myMap[0] = std::unique_ptr<Class1>(new Class1()); The difference between the two forms is that the former will fail if the key 0 … Read more
That is taking the parameter by reference. So in the first case you are taking a pointer parameter by reference so whatever modification you do to the value of the pointer is reflected outside the function. Second is the simlilar to first one with the only difference being that it is a double pointer. See … Read more
From the C99 standard (7.21.1/2): Where an argument declared as size_t n specifies the length of the array for a function, n can have the value zero on a call to that function. Unless explicitly stated otherwise in the description of a particular function in this subclause, pointer arguments on such a call shall still … Read more
You can’t treat arrays polymorphically, so while new B[100] creates an array of B objects and returns a pointer to the array – or equivalently the first element of the array – and while it is valid to assign this pointer to a pointer to a base class, it is not valid to treat this … Read more
this means pointer to the object, so *this is an object. So you are returning an object ie, *this returns a reference to the object.
In both C and C++ the only pointer literal or constant is zero. We can go to the draft C99 standard section 6.3.2.3 Pointers: An integer constant expression with the value 0, or such an expression cast to type void *, is called a null pointer constant.55) and: An integer may be converted to any … Read more
A string literal is a const char[] in C++, and may be stored in read-only memory so your program will crash if you try to modify it. Pointing a non-const pointer at it is a bad idea.
On storage duration: 2.13.4 Ordinary string literals and UTF-8 string literals are also referred to as narrow string literals. A narrow string literal has type “array of n const char”, where n is the size of the string as defined below, and has static storage duration read in conjunction with 3.7.1 3.7.1. All objects which … Read more
The asterisk belongs to the return type, and not to the function name, i.e.: void* func_name(void *param) { . . . . . } It means that the function returns a void pointer.
auto newvar1 = myvector; // vs: auto *newvar2 = myvector; Both of these are the same and will declare a pointer to std::vector<MyClass> (pointing to random location, since myvector is uninitialized in your example and likely contains garbage). So basically you can use any one of them. I would prefer auto var = getVector(), but … Read more