Boost C++ Libraries of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

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Copyright 2003 The Trustees of Indiana University

Authors: Jaakko Jarvi (jajarvi at
         Jeremiah Willcock (jewillco at
         Andrew Lumsdaine (lums at

Copyright 2018 Glen Joseph Fernandes

Distributed under the Boost Software License,
Version 1.0. (See accompanying file LICENSE_1_0.txt
or copy at

#include <boost/config.hpp>

namespace boost {

template<bool B, class T = void>
struct enable_if_ {
    typedef T type;

template<class T>
struct enable_if_<false, T> { };

template<bool B, class T = void>
using enable_if_t = typename enable_if_<B, T>::type;

} /* boost */