399 lines
15 KiB
C++
399 lines
15 KiB
C++
|
/*!
|
||
|
|
@file
|
||
|
|
Defines `boost::hana::map`.
|
||
|
|
|
||
|
|
@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_MAP_HPP
|
||
|
|
#define BOOST_HANA_MAP_HPP
|
||
|
|
|
||
|
|
#include <boost/hana/fwd/map.hpp>
|
||
|
|
|
||
|
|
#include <boost/hana/all_of.hpp>
|
||
|
|
#include <boost/hana/basic_tuple.hpp>
|
||
|
|
#include <boost/hana/bool.hpp>
|
||
|
|
#include <boost/hana/concept/comparable.hpp>
|
||
|
|
#include <boost/hana/concept/constant.hpp>
|
||
|
|
#include <boost/hana/concept/product.hpp>
|
||
|
|
#include <boost/hana/config.hpp>
|
||
|
|
#include <boost/hana/contains.hpp>
|
||
|
|
#include <boost/hana/core/is_a.hpp>
|
||
|
|
#include <boost/hana/core/make.hpp>
|
||
|
|
#include <boost/hana/core/to.hpp>
|
||
|
|
#include <boost/hana/detail/decay.hpp>
|
||
|
|
#include <boost/hana/detail/fast_and.hpp>
|
||
|
|
#include <boost/hana/detail/has_duplicates.hpp>
|
||
|
|
#include <boost/hana/detail/hash_table.hpp>
|
||
|
|
#include <boost/hana/detail/operators/adl.hpp>
|
||
|
|
#include <boost/hana/detail/operators/comparable.hpp>
|
||
|
|
#include <boost/hana/detail/operators/searchable.hpp>
|
||
|
|
#include <boost/hana/equal.hpp>
|
||
|
|
#include <boost/hana/find.hpp>
|
||
|
|
#include <boost/hana/first.hpp>
|
||
|
|
#include <boost/hana/fold_left.hpp>
|
||
|
|
#include <boost/hana/functional/demux.hpp>
|
||
|
|
#include <boost/hana/functional/on.hpp>
|
||
|
|
#include <boost/hana/functional/partial.hpp>
|
||
|
|
#include <boost/hana/fwd/any_of.hpp>
|
||
|
|
#include <boost/hana/fwd/at_key.hpp>
|
||
|
|
#include <boost/hana/fwd/erase_key.hpp>
|
||
|
|
#include <boost/hana/fwd/is_subset.hpp>
|
||
|
|
#include <boost/hana/fwd/keys.hpp>
|
||
|
|
#include <boost/hana/insert.hpp>
|
||
|
|
#include <boost/hana/integral_constant.hpp>
|
||
|
|
#include <boost/hana/keys.hpp>
|
||
|
|
#include <boost/hana/length.hpp>
|
||
|
|
#include <boost/hana/optional.hpp>
|
||
|
|
#include <boost/hana/remove_if.hpp>
|
||
|
|
#include <boost/hana/second.hpp>
|
||
|
|
#include <boost/hana/unpack.hpp>
|
||
|
|
#include <boost/hana/value.hpp>
|
||
|
|
|
||
|
|
#include <cstddef>
|
||
|
|
#include <type_traits>
|
||
|
|
#include <utility>
|
||
|
|
|
||
|
|
|
||
|
|
BOOST_HANA_NAMESPACE_BEGIN
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// operators
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
namespace detail {
|
||
|
|
template <>
|
||
|
|
struct comparable_operators<map_tag> {
|
||
|
|
static constexpr bool value = true;
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// map
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
//! @cond
|
||
|
|
namespace detail {
|
||
|
|
template <typename HashTable, typename Storage>
|
||
|
|
struct map_impl
|
||
|
|
: detail::searchable_operators<map_impl<HashTable, Storage>>
|
||
|
|
, detail::operators::adl<map_impl<HashTable, Storage>>
|
||
|
|
{
|
||
|
|
using hash_table_type = HashTable;
|
||
|
|
using storage_type = Storage;
|
||
|
|
|
||
|
|
Storage storage;
|
||
|
|
|
||
|
|
using hana_tag = map_tag;
|
||
|
|
|
||
|
|
template <typename ...P, typename = typename std::enable_if<
|
||
|
|
std::is_same<
|
||
|
|
Storage,
|
||
|
|
hana::basic_tuple<typename detail::decay<P>::type...>
|
||
|
|
>::value
|
||
|
|
>::type>
|
||
|
|
explicit constexpr map_impl(P&& ...pairs)
|
||
|
|
: storage{static_cast<P&&>(pairs)...}
|
||
|
|
{ }
|
||
|
|
|
||
|
|
explicit constexpr map_impl(Storage&& xs)
|
||
|
|
: storage(static_cast<Storage&&>(xs))
|
||
|
|
{ }
|
||
|
|
|
||
|
|
constexpr map_impl() = default;
|
||
|
|
constexpr map_impl(map_impl const& other) = default;
|
||
|
|
constexpr map_impl(map_impl&& other) = default;
|
||
|
|
};
|
||
|
|
//! @endcond
|
||
|
|
|
||
|
|
template <typename Storage>
|
||
|
|
struct KeyAtIndex {
|
||
|
|
template <std::size_t i>
|
||
|
|
using apply = decltype(hana::first(hana::get_impl<i>(std::declval<Storage>())));
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// make<map_tag>
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct make_impl<map_tag> {
|
||
|
|
template <typename ...Pairs>
|
||
|
|
static constexpr auto apply(Pairs&& ...pairs) {
|
||
|
|
#if defined(BOOST_HANA_CONFIG_ENABLE_DEBUG_MODE)
|
||
|
|
static_assert(detail::fast_and<hana::Product<Pairs>::value...>::value,
|
||
|
|
"hana::make_map(pairs...) requires all the 'pairs' to be Products");
|
||
|
|
|
||
|
|
static_assert(detail::fast_and<
|
||
|
|
hana::Comparable<decltype(hana::first(pairs))>::value...
|
||
|
|
>::value,
|
||
|
|
"hana::make_map(pairs...) requires all the keys to be Comparable");
|
||
|
|
|
||
|
|
static_assert(detail::fast_and<
|
||
|
|
hana::Constant<
|
||
|
|
decltype(hana::equal(hana::first(pairs), hana::first(pairs)))
|
||
|
|
>::value...
|
||
|
|
>::value,
|
||
|
|
"hana::make_map(pairs...) requires all the keys to be "
|
||
|
|
"Comparable at compile-time");
|
||
|
|
|
||
|
|
//! @todo
|
||
|
|
//! This can be implemented more efficiently by doing the check
|
||
|
|
//! inside each bucket instead.
|
||
|
|
static_assert(!detail::has_duplicates<decltype(hana::first(pairs))...>::value,
|
||
|
|
"hana::make_map({keys, values}...) requires all the keys to be unique");
|
||
|
|
|
||
|
|
static_assert(!detail::has_duplicates<decltype(hana::hash(hana::first(pairs)))...>::value,
|
||
|
|
"hana::make_map({keys, values}...) requires all the keys to have different hashes");
|
||
|
|
#endif
|
||
|
|
|
||
|
|
using Storage = hana::basic_tuple<typename detail::decay<Pairs>::type...>;
|
||
|
|
using HashTable = typename detail::make_hash_table<
|
||
|
|
detail::KeyAtIndex<Storage>::template apply, sizeof...(Pairs)
|
||
|
|
>::type;
|
||
|
|
|
||
|
|
return detail::map_impl<HashTable, Storage>{
|
||
|
|
hana::make_basic_tuple(static_cast<Pairs&&>(pairs)...)
|
||
|
|
};
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// keys
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct keys_impl<map_tag> {
|
||
|
|
template <typename Map>
|
||
|
|
static constexpr decltype(auto) apply(Map&& map) {
|
||
|
|
return hana::transform(static_cast<Map&&>(map).storage, hana::first);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// values
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
//! @cond
|
||
|
|
template <typename Map>
|
||
|
|
constexpr decltype(auto) values_t::operator()(Map&& map) const {
|
||
|
|
return hana::transform(static_cast<Map&&>(map).storage, hana::second);
|
||
|
|
}
|
||
|
|
//! @endcond
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// insert
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct insert_impl<map_tag> {
|
||
|
|
template <typename Map, typename Pair>
|
||
|
|
static constexpr auto helper(Map&& map, Pair&& pair, ...) {
|
||
|
|
using RawMap = typename std::remove_reference<Map>::type;
|
||
|
|
using HashTable = typename RawMap::hash_table_type;
|
||
|
|
using NewHashTable = typename detail::bucket_insert<
|
||
|
|
HashTable,
|
||
|
|
decltype(hana::first(pair)),
|
||
|
|
decltype(hana::length(map.storage))::value
|
||
|
|
>::type;
|
||
|
|
|
||
|
|
using NewStorage = decltype(
|
||
|
|
hana::append(static_cast<Map&&>(map).storage, static_cast<Pair&&>(pair))
|
||
|
|
);
|
||
|
|
return detail::map_impl<NewHashTable, NewStorage>(
|
||
|
|
hana::append(static_cast<Map&&>(map).storage, static_cast<Pair&&>(pair))
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Map, typename Pair, std::size_t i>
|
||
|
|
static constexpr auto
|
||
|
|
helper(Map&& map, Pair&&,
|
||
|
|
hana::optional<std::integral_constant<std::size_t, i>>)
|
||
|
|
{
|
||
|
|
return static_cast<Map&&>(map);
|
||
|
|
}
|
||
|
|
|
||
|
|
//! @todo
|
||
|
|
//! Here, we insert only if the key is not already in the map.
|
||
|
|
//! This should be handled by `bucket_insert`, and that would also
|
||
|
|
//! be more efficient.
|
||
|
|
template <typename Map, typename Pair>
|
||
|
|
static constexpr auto apply(Map&& map, Pair&& pair) {
|
||
|
|
using RawMap = typename std::remove_reference<Map>::type;
|
||
|
|
using Storage = typename RawMap::storage_type;
|
||
|
|
using HashTable = typename RawMap::hash_table_type;
|
||
|
|
using Key = decltype(hana::first(pair));
|
||
|
|
using MaybeIndex = typename detail::find_index<
|
||
|
|
HashTable, Key, detail::KeyAtIndex<Storage>::template apply
|
||
|
|
>::type;
|
||
|
|
return helper(static_cast<Map&&>(map), static_cast<Pair&&>(pair), MaybeIndex{});
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// erase_key
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct erase_key_impl<map_tag> {
|
||
|
|
//! @todo
|
||
|
|
//! We could implement some kind of `bucket_erase` metafunction
|
||
|
|
//! that would be much more efficient than this.
|
||
|
|
template <typename Map, typename Key>
|
||
|
|
static constexpr auto
|
||
|
|
erase_key_helper(Map&& map, Key const&, hana::false_) {
|
||
|
|
return static_cast<Map&&>(map);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Map, typename Key>
|
||
|
|
static constexpr auto
|
||
|
|
erase_key_helper(Map&& map, Key const& key, hana::true_) {
|
||
|
|
return hana::unpack(
|
||
|
|
hana::remove_if(static_cast<Map&&>(map).storage,
|
||
|
|
hana::on(hana::equal.to(key), hana::first)),
|
||
|
|
hana::make_map
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Map, typename Key>
|
||
|
|
static constexpr auto apply(Map&& map, Key const& key) {
|
||
|
|
constexpr bool contains = hana::value<decltype(hana::contains(map, key))>();
|
||
|
|
return erase_key_helper(static_cast<Map&&>(map), key,
|
||
|
|
hana::bool_c<contains>);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// Comparable
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct equal_impl<map_tag, map_tag> {
|
||
|
|
template <typename M1, typename M2>
|
||
|
|
static constexpr auto equal_helper(M1 const&, M2 const&, hana::false_) {
|
||
|
|
return hana::false_c;
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename M1, typename M2>
|
||
|
|
static constexpr auto equal_helper(M1 const& m1, M2 const& m2, hana::true_) {
|
||
|
|
return hana::all_of(hana::keys(m1), hana::demux(equal)(
|
||
|
|
hana::partial(hana::find, m1),
|
||
|
|
hana::partial(hana::find, m2)
|
||
|
|
));
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename M1, typename M2>
|
||
|
|
static constexpr auto apply(M1 const& m1, M2 const& m2) {
|
||
|
|
return equal_impl::equal_helper(m1, m2, hana::bool_c<
|
||
|
|
decltype(hana::length(m1.storage))::value ==
|
||
|
|
decltype(hana::length(m2.storage))::value
|
||
|
|
>);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// Searchable
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct find_impl<map_tag> {
|
||
|
|
template <typename Map>
|
||
|
|
static constexpr auto find_helper(Map&&, ...) {
|
||
|
|
return hana::nothing;
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Map, std::size_t i>
|
||
|
|
static constexpr auto
|
||
|
|
find_helper(Map&& map, hana::optional<std::integral_constant<std::size_t, i>>) {
|
||
|
|
return hana::just(hana::second(hana::at_c<i>(static_cast<Map&&>(map).storage)));
|
||
|
|
}
|
||
|
|
|
||
|
|
template <typename Map, typename Key>
|
||
|
|
static constexpr auto apply(Map&& map, Key const&) {
|
||
|
|
using RawMap = typename std::remove_reference<Map>::type;
|
||
|
|
using Storage = typename RawMap::storage_type;
|
||
|
|
using HashTable = typename RawMap::hash_table_type;
|
||
|
|
using MaybeIndex = typename detail::find_index<
|
||
|
|
HashTable, Key, detail::KeyAtIndex<Storage>::template apply
|
||
|
|
>::type;
|
||
|
|
return find_helper(static_cast<Map&&>(map), MaybeIndex{});
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
template <>
|
||
|
|
struct find_if_impl<map_tag> {
|
||
|
|
template <typename M, typename Pred>
|
||
|
|
static constexpr auto apply(M&& map, Pred&& pred) {
|
||
|
|
return hana::transform(
|
||
|
|
hana::find_if(static_cast<M&&>(map).storage,
|
||
|
|
hana::compose(static_cast<Pred&&>(pred), hana::first)),
|
||
|
|
hana::second
|
||
|
|
);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
template <>
|
||
|
|
struct any_of_impl<map_tag> {
|
||
|
|
template <typename M, typename Pred>
|
||
|
|
static constexpr auto apply(M const& map, Pred const& pred)
|
||
|
|
{ return hana::any_of(hana::keys(map), pred); }
|
||
|
|
};
|
||
|
|
|
||
|
|
template <>
|
||
|
|
struct is_subset_impl<map_tag, map_tag> {
|
||
|
|
template <typename Ys>
|
||
|
|
struct all_contained {
|
||
|
|
Ys const& ys;
|
||
|
|
template <typename ...X>
|
||
|
|
constexpr auto operator()(X const& ...x) const {
|
||
|
|
return hana::bool_c<detail::fast_and<
|
||
|
|
hana::value<decltype(hana::contains(ys, x))>()...
|
||
|
|
>::value>;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
template <typename Xs, typename Ys>
|
||
|
|
static constexpr auto apply(Xs const& xs, Ys const& ys) {
|
||
|
|
auto ys_keys = hana::keys(ys);
|
||
|
|
return hana::unpack(hana::keys(xs), all_contained<decltype(ys_keys)>{ys_keys});
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
template <>
|
||
|
|
struct at_key_impl<map_tag> {
|
||
|
|
template <typename Map, typename Key>
|
||
|
|
static constexpr decltype(auto) apply(Map&& map, Key const&) {
|
||
|
|
using RawMap = typename std::remove_reference<Map>::type;
|
||
|
|
using HashTable = typename RawMap::hash_table_type;
|
||
|
|
using Storage = typename RawMap::storage_type;
|
||
|
|
using MaybeIndex = typename detail::find_index<
|
||
|
|
HashTable, Key, detail::KeyAtIndex<Storage>::template apply
|
||
|
|
>::type;
|
||
|
|
static_assert(!decltype(hana::is_nothing(MaybeIndex{}))::value,
|
||
|
|
"hana::at_key(map, key) requires the 'key' to be present in the 'map'");
|
||
|
|
constexpr std::size_t index = decltype(*MaybeIndex{}){}();
|
||
|
|
return hana::second(hana::at_c<index>(static_cast<Map&&>(map).storage));
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// Foldable
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <>
|
||
|
|
struct unpack_impl<map_tag> {
|
||
|
|
template <typename M, typename F>
|
||
|
|
static constexpr decltype(auto) apply(M&& map, F&& f) {
|
||
|
|
return hana::unpack(static_cast<M&&>(map).storage,
|
||
|
|
static_cast<F&&>(f));
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
// Construction from a Foldable
|
||
|
|
//////////////////////////////////////////////////////////////////////////
|
||
|
|
template <typename F>
|
||
|
|
struct to_impl<map_tag, F, when<hana::Foldable<F>::value>> {
|
||
|
|
template <typename Xs>
|
||
|
|
static constexpr decltype(auto) apply(Xs&& xs) {
|
||
|
|
return hana::fold_left(
|
||
|
|
static_cast<Xs&&>(xs), hana::make_map(), hana::insert
|
||
|
|
);
|
||
|
|
}
|
||
|
|
};
|
||
|
|
BOOST_HANA_NAMESPACE_END
|
||
|
|
|
||
|
|
#endif // !BOOST_HANA_MAP_HPP
|