cpp/named req/UnaryTypeTrait

A is a class template that describes a property of its template type parameter with an  (typically ) specialization.

Requirements

 * and
 * Takes one template type parameter (additional template parameters are optional and allowed)
 * Publicly and unambiguously derived from a specialization of, known as its base characteristic
 * The member names of the base characteristic are not hidden and are unambiguously available

Standard library
The following type properties all satisfy.
 * Primary type categories
 * Composite type categories
 * Type properties
 * Supported operations
 * Property queries

The following standard library class templates also satisfy.