added o.map()

This commit is contained in:
Andrzej Krzemienski
2018-06-23 18:27:14 +02:00
parent 5182f7f30f
commit e47a017009
50 changed files with 343 additions and 91 deletions

View File

@ -1,4 +1,4 @@
// Copyright (C) 2015-2016 Andrzej Krzemienski.
// Copyright (C) 2015-2018 Andrzej Krzemienski.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -161,6 +161,15 @@ public:
bool is_initialized() const BOOST_NOEXCEPT { return ptr_ != 0; }
bool has_value() const BOOST_NOEXCEPT { return ptr_ != 0; }
template <typename F>
optional<typename boost::result_of<F(T&)>::type> map(F f) const
{
if (this->has_value())
return f(this->get());
else
return none;
}
#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
optional(T&& /* rhs */) BOOST_NOEXCEPT { detail::prevent_binding_rvalue<T&&>(); }