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### has_trivial_copy

    template <class T>
    struct has_trivial_copy : public true_type-or-false_type {};

    template <class T>
    struct has_trivial_copy_constructor : public true_type-or-false_type {};

Inherits: If T is a (possibly cv-qualified) type with a trivial copy-constructor then inherits from true_type, otherwise inherits from false_type.

These two traits are synonyms for each other.

If a type has a trivial copy-constructor then the constructor has the same effect as copying the bits of one object to the other: calls to the constructor can be safely replaced with a call to `memcpy`.

Compiler Compatibility: If the compiler does not support partial-specialization of class templates, then this template can not be used with function types.

Without some (as yet unspecified) help from the compiler, has_trivial_copy will never report that a user-defined class or struct has a trivial constructor; this is always safe, if possibly sub-optimal. Currently (May 2005) only MWCW 9 and Visual C++ 8 have the necessary compiler intrinsics to detect user-defined classes with trivial constructors.

C++ Standard Reference: 12.8p6.

Header: `#include <boost/type_traits/has_trivial_copy.hpp>` or `#include <boost/type_traits.hpp>`

Examples:

> `has_trivial_copy<int>` inherits from `true_type`.

> `has_trivial_copy<char*>::type` is the type `true_type`.

> `has_trivial_copy<int (*)(long)>::value` is an integral constant expression that evaluates to true.

> `has_trivial_copy<MyClass>::value` is an integral constant expression that evaluates to false.

> `has_trivial_copy<T>::value_type` is the type `bool`.