1 files changed, 175 insertions, 0 deletions
diff --git a/boost/mp11/utility.hpp b/boost/mp11/utility.hpp
new file mode 100644
index 0000000000..5935e6da79
--- /dev/null
+++ b/boost/mp11/utility.hpp
@@ -0,0 +1,175 @@
+#ifndef BOOST_MP11_UTILITY_HPP_INCLUDED
+#define BOOST_MP11_UTILITY_HPP_INCLUDED
+
+//  Copyright 2015, 2017 Peter Dimov.
+//
+//  Distributed under the Boost Software License, Version 1.0.
+//
+//  See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/mp11/integral.hpp>
+#include <boost/config.hpp>
+#include <boost/detail/workaround.hpp>
+
+namespace boost
+{
+namespace mp11
+{
+
+// mp_identity
+template<class T> struct mp_identity
+{
+    using type = T;
+};
+
+// mp_identity_t
+template<class T> using mp_identity_t = typename mp_identity<T>::type;
+
+// mp_inherit
+template<class... T> struct mp_inherit: T... {};
+
+// mp_if, mp_if_c
+namespace detail
+{
+
+template<bool C, class T, class... E> struct mp_if_c_impl
+{
+};
+
+template<class T, class... E> struct mp_if_c_impl<true, T, E...>
+{
+    using type = T;
+};
+
+template<class T, class E> struct mp_if_c_impl<false, T, E>
+{
+    using type = E;
+};
+
+} // namespace detail
+
+template<bool C, class T, class... E> using mp_if_c = typename detail::mp_if_c_impl<C, T, E...>::type;
+template<class C, class T, class... E> using mp_if = typename detail::mp_if_c_impl<static_cast<bool>(C::value), T, E...>::type;
+
+// mp_valid
+// implementation by Bruno Dutra (by the name is_evaluable)
+namespace detail
+{
+
+template<template<class...> class F, class... T> struct mp_valid_impl
+{
+    template<template<class...> class G, class = G<T...>> static mp_true check(int);
+    template<template<class...> class> static mp_false check(...);
+
+    using type = decltype(check<F>(0));
+};
+
+} // namespace detail
+
+template<template<class...> class F, class... T> using mp_valid = typename detail::mp_valid_impl<F, T...>::type;
+
+// mp_defer
+namespace detail
+{
+
+template<template<class...> class F, class... T> struct mp_defer_impl
+{
+    using type = F<T...>;
+};
+
+struct mp_no_type
+{
+};
+
+} // namespace detail
+
+template<template<class...> class F, class... T> using mp_defer = mp_if<mp_valid<F, T...>, detail::mp_defer_impl<F, T...>, detail::mp_no_type>;
+
+// mp_eval_if, mp_eval_if_c
+namespace detail
+{
+
+template<bool C, class T, template<class...> class F, class... U> struct mp_eval_if_c_impl;
+
+template<class T, template<class...> class F, class... U> struct mp_eval_if_c_impl<true, T, F, U...>
+{
+    using type = T;
+};
+
+template<class T, template<class...> class F, class... U> struct mp_eval_if_c_impl<false, T, F, U...>: mp_defer<F, U...>
+{
+};
+
+} // namespace detail
+
+template<bool C, class T, template<class...> class F, class... U> using mp_eval_if_c = typename detail::mp_eval_if_c_impl<C, T, F, U...>::type;
+template<class C, class T, template<class...> class F, class... U> using mp_eval_if = typename detail::mp_eval_if_c_impl<static_cast<bool>(C::value), T, F, U...>::type;
+template<class C, class T, class Q, class... U> using mp_eval_if_q = typename detail::mp_eval_if_c_impl<static_cast<bool>(C::value), T, Q::template fn, U...>::type;
+
+// mp_cond
+
+// so elegant; so doesn't work
+// template<class C, class T, class... E> using mp_cond = mp_eval_if<C, T, mp_cond, E...>;
+
+namespace detail
+{
+
+template<class C, class T, class... E> struct mp_cond_impl;
+
+} // namespace detail
+
+template<class C, class T, class... E> using mp_cond = typename detail::mp_cond_impl<C, T, E...>::type;
+
+namespace detail
+{
+
+template<class C, class T, class... E> using mp_cond_ = mp_eval_if<C, T, mp_cond, E...>;
+
+template<class C, class T, class... E> struct mp_cond_impl: mp_defer<mp_cond_, C, T, E...>
+{
+};
+
+} // namespace detail
+
+// mp_quote
+template<template<class...> class F> struct mp_quote
+{
+    // the indirection through mp_defer works around the language inability
+    // to expand T... into a fixed parameter list of an alias template
+
+    template<class... T> using fn = typename mp_defer<F, T...>::type;
+};
+
+// mp_quote_trait
+template<template<class...> class F> struct mp_quote_trait
+{
+    template<class... T> using fn = typename F<T...>::type;
+};
+
+// mp_invoke
+#if BOOST_WORKAROUND( BOOST_MSVC, < 1900 )
+
+namespace detail
+{
+
+template<class Q, class... T> struct mp_invoke_impl: mp_defer<Q::template fn, T...> {};
+
+} // namespace detail
+
+template<class Q, class... T> using mp_invoke = typename detail::mp_invoke_impl<Q, T...>::type;
+
+#elif BOOST_WORKAROUND( BOOST_GCC, < 50000 )
+
+template<class Q, class... T> using mp_invoke = typename mp_defer<Q::template fn, T...>::type;
+
+#else
+
+template<class Q, class... T> using mp_invoke = typename Q::template fn<T...>;
+
+#endif
+
+} // namespace mp11
+} // namespace boost
+
+#endif // #ifndef BOOST_MP11_UTILITY_HPP_INCLUDED