std::is_integral
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <type_traits> | ||
| template< class T > struct is_integral; | (since C++11) | |
Checks whether T is an integral type. Provides the member constant value which is equal to true, if T is the type bool, char, char16_t, char32_t, wchar_t, short, int, long, long long, or any implementation-defined extended integer types, including any signed, unsigned, and cv-qualified variants. Otherwise, value is equal to false.
| Contents | 
[edit] Template parameters
| T | - | a type to check | 
[edit] Helper variable template
| template< class T > inline constexpr bool is_integral_v = is_integral<T>::value; | (since C++17) | |
Inherited from std::integral_constant
Member constants
| value [static] | true if Tis an integral type , false otherwise(public static member constant) | 
Member functions
| operator bool | converts the object to bool, returns value(public member function) | 
| operator() (C++14) | returns value(public member function) | 
Member types
| Type | Definition | 
| value_type | bool | 
| type | std::integral_constant<bool, value> | 
[edit] Example
Run this code
#include <iostream> #include <type_traits> class A {}; template <class T> T f(T i) { static_assert(std::is_integral<T>::value, "Integer required."); return i; } int main() { std::cout << std::boolalpha; std::cout << std::is_integral<A>::value << '\n'; std::cout << std::is_integral<float>::value << '\n'; std::cout << std::is_integral<int>::value << '\n'; std::cout << f(123) << '\n'; }
Output:
false false true 123
[edit] See also
| [static] | identifies integer types (public static member constant of std::numeric_limits) | 
| (C++11) | checks if a type is floating-point type (class template) | 
| (C++11) | checks if a type is arithmetic type (class template) | 


