has_trivial_destructor

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### has_trivial_destructor

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

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

If a type has a trivial destructor then the destructor has no effect: calls to the destructor can be safely omitted. Note that using meta-programming to omit a call to a single trivial-constructor call is of no benefit whatsoever. However, if loops and/or exception handling code can also be omitted, then some benefit in terms of code size and speed can be obtained.

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_destructor will never report that a user-defined class or struct has a trivial destructor; 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: 12.4p3.

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

Examples:

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

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

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

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

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