84 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++1110// <utility>11 12// class make_integer_sequence13 14#include <tuple>15#include <utility>16#include <type_traits>17#include <cassert>18 19#include "test_macros.h"20 21template <typename AtContainer, typename T, T... I>22auto extract ( const AtContainer &t, const std::integer_sequence<T, I...> )23-> decltype ( std::make_tuple ( std::get<I>(t)... ))24{ return std::make_tuple ( std::get<I>(t)... ); }25 26int main(int, char**)27{28// Make a couple of sequences29 using int3 = std::make_integer_sequence<int, 3>; // generates int: 0,1,230 using size7 = std::make_integer_sequence<std::size_t, 7>; // generates size_t: 0,1,2,3,4,5,631 using size4 = std::make_index_sequence<4>; // generates size_t: 0,1,2,332 using size2 = std::index_sequence_for<int, std::size_t>; // generates size_t: 0,133 using intmix = std::integer_sequence<int, 9, 8, 7, 2>; // generates int: 9,8,7,234 using sizemix = std::index_sequence<1, 1, 2, 3, 5>; // generates size_t: 1,1,2,3,535 36// Make sure they're what we expect37 static_assert ( std::is_same<int3::value_type, int>::value, "int3 type wrong" );38 static_assert ( int3::size () == 3, "int3 size wrong" );39 40 static_assert ( std::is_same<size7::value_type, std::size_t>::value, "size7 type wrong" );41 static_assert ( size7::size () == 7, "size7 size wrong" );42 43 static_assert ( std::is_same<size4::value_type, std::size_t>::value, "size4 type wrong" );44 static_assert ( size4::size () == 4, "size4 size wrong" );45 46 static_assert ( std::is_same<size2::value_type, std::size_t>::value, "size2 type wrong" );47 static_assert ( size2::size () == 2, "size2 size wrong" );48 49 static_assert ( std::is_same<intmix::value_type, int>::value, "intmix type wrong" );50 static_assert ( intmix::size () == 4, "intmix size wrong" );51 52 static_assert ( std::is_same<sizemix::value_type, std::size_t>::value, "sizemix type wrong" );53 static_assert ( sizemix::size () == 5, "sizemix size wrong" );54 55 auto tup = std::make_tuple ( 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 );56 57// Use them58 auto t3 = extract ( tup, int3() );59 static_assert ( std::tuple_size<decltype(t3)>::value == int3::size (), "t3 size wrong");60 assert ( t3 == std::make_tuple ( 10, 11, 12 ));61 62 auto t7 = extract ( tup, size7 ());63 static_assert ( std::tuple_size<decltype(t7)>::value == size7::size (), "t7 size wrong");64 assert ( t7 == std::make_tuple ( 10, 11, 12, 13, 14, 15, 16 ));65 66 auto t4 = extract ( tup, size4 ());67 static_assert ( std::tuple_size<decltype(t4)>::value == size4::size (), "t4 size wrong");68 assert ( t4 == std::make_tuple ( 10, 11, 12, 13 ));69 70 auto t2 = extract ( tup, size2 ());71 static_assert ( std::tuple_size<decltype(t2)>::value == size2::size (), "t2 size wrong");72 assert ( t2 == std::make_tuple ( 10, 11 ));73 74 auto tintmix = extract ( tup, intmix ());75 static_assert ( std::tuple_size<decltype(tintmix)>::value == intmix::size (), "tintmix size wrong");76 assert ( tintmix == std::make_tuple ( 19, 18, 17, 12 ));77 78 auto tsizemix = extract ( tup, sizemix ());79 static_assert ( std::tuple_size<decltype(tsizemix)>::value == sizemix::size (), "tsizemix size wrong");80 assert ( tsizemix == std::make_tuple ( 11, 11, 12, 13, 15 ));81 82 return 0;83}84