std::experimental::ranges::SignedIntegral
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                    | Defined in header  <experimental/ranges/concepts> | ||
| template < class T > concept bool SignedIntegral = Integral<T> && std::is_signed<T>::value; | (ranges TS) | |
The concept SignedIntegral<T> is satisfied if and only if T is an integral type and std::is_signed<T>::value is true.
There need not be any subsumption relationship between SignedIntegral<T> and std::is_signed<T>::value. 
Notes
SignedIntegral<T> may be satisfied by a type that is not a signed integer type, for example, char (on a system where char is signed).
See also
| (C++11) | checks if a type is an integral type (class template) | 
| (C++11) | checks if a type is a signed arithmetic type (class template) |