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### is_copy_constructible

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

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

In other words, inherits from true_type only if copy constructor of `T` not marked with `= delete`, `T` does not derives from `boost::noncopyable` and does not marked with `BOOST_MOVABLE_BUT_NOT_COPYABLE(T)`.

Compiler Compatibility: This trait requires the C++11 features `decltype` and SFINAE-expression support for full support.

If your compiler does not support C++11 deleted functions (`= delete`) or does not support SFINAE for the deleted constructors, then derive your classes from `boost::noncopyable` or mark them with `BOOST_MOVABLE_BUT_NOT_COPYABLE(T)` to show that class is noncopyable.

The trait does not care about access modifiers, so if you see errors like this:

    'T::T(const T&)' is private
    boost/type_traits/is_copy_constructible.hpp:68:5: error: within this context

then you are trying to call that macro for a structure with private constructor:

    struct T {
        // ...
    private:
        T(const T &);
        // ...
    };

To fix that you must modify your structure, explicitly marking it as noncopyable (`= delete`, `boost::noncopyable` or `BOOST_MOVABLE_BUT_NOT_COPYABLE(T)`) or explicitly specialize trait.

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