std::string::back() in C++ with Examples

std::add_const in C++ with Examples

Last Updated : 12 Jun, 2020

The std::add_const template of C++ STL is present in the <type_traits> header file. The std::add_const template of C++ STL is used to get the type T with const qualification. The std::is_volatile is used to check if type T is const qualified or not. Header File:

#include<type_traits>

Template Class:

template < class T >
struct add_const;

Syntax:

std::add_const<T>::value

Parameter: The template std::add_const accepts a single parameter T(Trait class) which is used to declare the type T as a const qualified. Below is the program to demonstrate std::add_const: in C++: Program:

CPP

// C++ program to illustrate
// std::add_const
#include <bits/stdc++.h>
#include <type_traits>
using namespace std;

// Driver Code
int main()
{

    // Declare variable of type
    // int, const int, const int*,
    // int * const and const int&
    typedef add_const<int>::type A;
    typedef add_const<const int>::type B;
    typedef add_const<const int*>::type C;
    typedef add_const<int* const>::type D;
    typedef add_const<const int&>::type E;

    cout << std::boolalpha;

    // Checking const of the above
    // declared variables
    cout << "A is const int? "
         << is_same<const int, A>::value
         << endl;

    cout << "B is const int? "
         << is_same<const int, B>::value
         << endl;

    cout << "C is const int? "
         << is_same<const int, C>::value
         << endl;

    cout << "D is const int? "
         << is_same<const int, D>::value
         << endl;

    std::cout << "E is const int? "
              << is_same<const int, E>::value
              << endl;

    return 0;
}

Output:

A is const int? true
B is const int? true
C is const int? false
D is const int? false
E is const int? false

Reference: http://www.cplusplus.com/reference/type_traits/add_const/

std::string::back() in C++ with Examples

bansal_rtk_

Improve

Article Tags :

Practice Tags :

Similar Reads

std::add_cv in C++ with Examples

The std::add_cv template of C++ STL is present in the <type_traits> header file. The std::add_cv template of C++ STL is used to get the type T with const and volatile qualification. The function std::is_same::value is used to check whether T is a const and volatile qualification or not. Header

std::to_address in C++ with Examples

The std::to_address, introduced in C++20, is used to obtain the address represented by the specified pointer without forming a reference to the pointee. The existing std::addressof cannot do std::addressof(*ptr) because *ptr isnâ€™t always an object. The std::to_address solves these issues for us. Syn

std::add_volatile in C++ with Examples

The std::add_volatile template of C++ STL is present in the <type_traits> header file. The std::add_volatile template of C++ STL is used to get the type T with volatile qualification. The function std::is_volatile is used to check if type T is volatile qualified or not. Header File: #include

std::allocator() in C++ with Examples

Allocators are objects responsible for encapsulating memory management. std::allocator is used when you want to separate allocation and do construction in two steps. It is also used when separate destruction and deallocation is done in two steps. All the STL containers in C++ have a type parameter A

std::string::back() in C++ with Examples

This function returns a direct reference to the last character of the string. This shall only be used on non-empty strings. This can be used to access the last character of the string as well as to append a character at the end of the string. Length of the string remains unchanged after appending a

std::is_copy_assignable in C++ with Examples

The std::is_copy_assignable template of C++ STL is present in the <type_traits> header file. The std::is_copy_assignable template of C++ STL is used to check whether the T is copy assignable or not. It return the boolean value true if T is copy assignable type, otherwise return false. Header F

Storage Classes in C++ with Examples

C++ Storage Classes are used to describe the characteristics of a variable/function. It determines the lifetime, visibility, default value, and storage location which helps us to trace the existence of a particular variable during the runtime of a program. Storage class specifiers are used to specif

std::remove_cv in C++ with Example

The std::remove_cv template of C++ STL is present in the <type_traits> header file. The std::remove_cv template of C++ STL is used to get the type T without const and volatile qualification. It return the boolean value true if T is without const and volatile qualified, otherwise return false.

conj() function in C++ with Examples

The conj() function is defined in the complex header file. This function is used to find the conjugate of the complex number z. If we represent a complex number z as (real, img), then its conjugate is (real, -img).Syntax: template<class T> complex<T> conj (const complex<T>& Z);

std::add_lvalue_reference in C++ with Examples

The std::add_lvalue_reference template of C++ STL is present in the <type_traits> header file. The std::add_lvalue_reference template of C++ STL is used to get lvalue reference type that refers to T type. An lvalue reference is formed by placing an '&' after some type. An rvalue reference