A std::array isn’t limited to elements of fundamental types. Rather, the elements of a std::array can be any object type, including compound types. This means you can create a std::array of pointers, or a std::array of structs (or classes) However, initializing a std::array of structs or classes tends to trip …
An object of type std::array can be passed to a function just like any other object. That means if we pass a std::array by value, an expensive copy will be made. Therefore, we typically pass std::array by (const) reference to avoid such copies. With a std::array, both the element type …
In lesson , we discussed the unfortunate decision to make the standard library container classes use unsigned values for lengths and indices. Because std::array is a standard library container class, it is subject to the same issues. In this lesson, we’ll recap ways to index and get the length of …
Words of encouragement This chapter isn’t an easy one. We covered a lot of material, and unearthed some of C++’s warts. Congrats on making it through! Arrays are one of the keys that unlock a huge amount of power within your C++ programs. Chapter Review A container is a data …
In lesson , we discussed how std::bitset has the capability to compact 8 Boolean values into a byte. Those bits can then be modified via the member functions of std::bitset. std::vector has an interesting trick up its sleeves. There is a special implementation for std::vector<bool> that may be more space …
Consider the case where you are writing a program where the user will enter a list of values (such as a bunch of test scores). In this case, the number of values that they will be entering is not known at compile time, and could vary every time they run …
One of the bigger documentation problems with arrays is that integer indices do not provide any information to the programmer about the meaning of the index. Consider an array holding 5 test scores: #include <vector> int main() { std::vector testScores { 78, 94, 66, 77, 14 }; testScores[2] = 76; …
In lesson , we noted how we generally prefer to use signed values to hold quantities, because unsigned values can act in surprising ways. However, in lesson , we discussed how std::vector (and other container classes) uses unsigned integral type std::size_t for length and indices. This can lead to problems …
In the prior lesson , we introduced operator[], which can be used to subscript an array to access an element. In this lesson, we’ll look at other ways to access array elements, as well as a few different ways to get the length of an container class (the number of …
An object of type std::vector can be passed to a function just like any other object. That means if we pass a std::vector by value, an expensive copy will be made. Therefore, we typically pass std::vector by (const) reference to avoid such copies. With a std::vector, the element type is …
