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Diffstat (limited to 'boost/hana/fwd/fill.hpp')
| -rw-r--r-- | boost/hana/fwd/fill.hpp | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/boost/hana/fwd/fill.hpp b/boost/hana/fwd/fill.hpp new file mode 100644 index 0000000000..38a4a35c96 --- /dev/null +++ b/boost/hana/fwd/fill.hpp @@ -0,0 +1,57 @@ +/*! +@file +Forward declares `boost::hana::fill`. + +@copyright Louis Dionne 2013-2016 +Distributed under the Boost Software License, Version 1.0. +(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) + */ + +#ifndef BOOST_HANA_FWD_FILL_HPP +#define BOOST_HANA_FWD_FILL_HPP + +#include <boost/hana/config.hpp> +#include <boost/hana/core/when.hpp> + + +BOOST_HANA_NAMESPACE_BEGIN + //! Replace all the elements of a structure with a fixed value. + //! @ingroup group-Functor + //! + //! + //! Signature + //! --------- + //! Given `F` a Functor, the signature is + //! \f$ + //! \mathtt{fill} : F(T) \times U \to F(U) + //! \f$ + //! + //! @param xs + //! The structure to fill with a `value`. + //! + //! @param value + //! A value by which every element `x` of the structure is replaced, + //! unconditionally. + //! + //! + //! Example + //! ------- + //! @include example/fill.cpp +#ifdef BOOST_HANA_DOXYGEN_INVOKED + constexpr auto fill = [](auto&& xs, auto&& value) { + return tag-dispatched; + }; +#else + template <typename Xs, typename = void> + struct fill_impl : fill_impl<Xs, when<true>> { }; + + struct fill_t { + template <typename Xs, typename Value> + constexpr auto operator()(Xs&& xs, Value&& value) const; + }; + + constexpr fill_t fill{}; +#endif +BOOST_HANA_NAMESPACE_END + +#endif // !BOOST_HANA_FWD_FILL_HPP |