[libc++] Remove default_searcher from experimental/functional

[jloser]

Summary

std::default_searcher has been implemented for a while now
(introduced in d835e59211883) - far more than two llvm releases. So, remove it
and std::experimental::make_default_searcher from <experimental/functional>.

There already exists tests for std::default_searcher in
libcxx/test/std/utilities/function.objects/func.search/func.search.default, so
there is no loss in test coverage.

[jloser]

Update synopsis in experimental/functional

[philnik]

Would you be interested in looking into the other stuff defined in the header? I'm guessing that these things can also be removed.

[jloser]

In D119198#3303066, @philnik wrote:

Would you be interested in looking into the other stuff defined in the header? I'm guessing that these things can also be removed.

Yep, I have a follow-up planned for booyer moore searcher. We already have those tests XFAILed for libc++ for std::booyer_moore_searcher. :)

[ldionne]

LGTM, but please add a release note mentioning the removal.

libcxx/include/experimental/functional

106–107

Please don't bump the standard version in this patch, since it's technically an unrelated change (IIUC).

[jloser]

Add release note

libcxx/include/experimental/functional

106–107

It's required if we want make_default_searcher to work at all since std::default_searcher is C++17-or-later only (https://github.com/llvm/llvm-project/blob/main/libcxx/include/__functional/default_searcher.h#L25). Otherwise, we can't remove std::experimental::default_searcher if we want these to work in C++14-or-later and not C++17-or-later.

We could remove make_default_searcher entirely, but I think that'd be for a separate patch and I don't see the reason to do so right now.

[• Quuxplusone]

libcxx/include/experimental/functional

106–107

If you're removing std::experimental::default_searcher, you should definitely remove std::experimental::make_default_searcher at the same time. The two are tied inextricably together — what you've got now is analogous to removing std::tr1::shared_ptr but keeping std::tr1::weak_ptr!

Think about the user experience here: as a user of std::experimental::{make_,}default_searcher, would you rather have the whole thing yanked, or would you rather have std::experimental::make_default_searcher yanked only in C++14 mode, and in C++17 mode produce a different return type than it used to? Yanking the whole thing will be much saner from the user's POV.

107

Orthogonally: What's the deal with std::experimental::boyer_moore_searcher? Have we implemented std::boyer_moore_searcher https://en.cppreference.com/w/cpp/utility/functional/boyer_moore_searcher yet? (No. We haven't.)

Ordering-wise, it would sure have made a lot more sense for us to have implemented std::boyer_moore_{,horspool_}searcher all at once, and then we could yank std::experimental::*_searcher all at once. The current state — where you need std::experimental:: for two of the searchers, but (@jloser proposes) you'll need std:: for the other one — seems really unfortunate to me. But the time for us to fix that was 2 releases ago; it's not @jloser's fault that we didn't do it, and so maybe it shouldn't stop us from removing deprecated features according to schedule.

[jloser]

Remove std::experimental::make_default_searcher and update release note to reflect this

[jloser]

libcxx/include/experimental/functional

106–107

Valid argument. I've removed std::experimental::make_default_searcher.

107

Agree re the ordering. We could take std::experimental::boyer_moore_{,horspool_}searcher and figure out the loose ends to put them into std and then remove all the searchers from experimental/functional at once. If we do that, then I'll close this PR, and I might volunteer to implement the searchers into std to complete the work effectively. The alternative is to piecemeal the removals by doing just default_searcher and make_default_searcher since std::default_searcher already is implemented today, which is what this PR is.

@ldionne thoughts on piecemeal removal vs all-at-once? I don't think I'd get to the other searchers for a little while if we want to do the all-at-once approach.

[ldionne]

libcxx/include/experimental/functional

107

I have to agree with Arthur here -- if a user sees that we removed std::experimental::default_searcher, the next thing they will try to do is migrate any uses of std::experimental::boyer_moore_searcher to std::boyer_moore_searcher, only to see that fail. If we don't remove all at once, we're creating churn for the users, and I think we'd like to avoid that. Sorry I didn't catch it before, but I think the right call would be not to remove those at all until we can remove all of them in favour of the std:: version.

[jloser]

This work is already done - abandoning this patch.

libcxx/docs/ReleaseNotes.rst

 ============================
 
 New Features
 ------------
 
 API Changes
 -----------
 
+- ``std::experimental::default_searcher` and ``std::experimental::make_default_searcher``
+  have been removed from ``<experimental/functional>``. Use ``std::default_searcher``
+  from ``<functional>`` instead which requires C++17.
+
 ABI Changes
 -----------
 
 - The ``_LIBCPP_ABI_USE_CXX03_NULLPTR_EMULATION`` macro controlling whether we use an
   emulation for ``std::nullptr_t`` in C++03 mode has been removed. After this change,
   ``_LIBCPP_ABI_USE_CXX03_NULLPTR_EMULATION`` will not be honoured anymore and there
   will be no way to opt back into the C++03 emulation of ``std::nullptr_t``.
 
 Build System Changes
 --------------------

libcxx/include/experimental/functional

inline namespace fundamentals_v1 {
     template<class R, class... ArgTypes>
     bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
     template<class R, class... ArgTypes>
     bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept;
     template<class R, class... ArgTypes>
     bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept;
 
     // 4.3, Searchers
-    template<class ForwardIterator, class BinaryPredicate = equal_to<>>
-      class default_searcher;
-
     template<class RandomAccessIterator,
              class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>,
              class BinaryPredicate = equal_to<>>
       class boyer_moore_searcher;
 
     template<class RandomAccessIterator,
              class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>,
              class BinaryPredicate = equal_to<>>
inline namespace fundamentals_v1 {
   template<class R, class... ArgTypes, class Alloc>
   struct uses_allocator<experimental::function<R(ArgTypes...)>, Alloc>;
 
 } // namespace std
 
 */
 
 #include <__debug>
+#include <__functional/default_searcher.h>
 #include <__memory/uses_allocator.h>
 #include <algorithm>
 #include <array>
 #include <experimental/__config>
 #include <functional>
 #include <type_traits>
 #include <unordered_map>
 #include <vector>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>
 
 _LIBCPP_BEGIN_NAMESPACE_LFTS
 
 #if _LIBCPP_STD_VER > 11
-// default searcher
-template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
-class _LIBCPP_TEMPLATE_VIS default_searcher {
-public:
-    _LIBCPP_INLINE_VISIBILITY
-    default_searcher(_ForwardIterator __f, _ForwardIterator __l,
-                       _BinaryPredicate __p = _BinaryPredicate())
-        : __first_(__f), __last_(__l), __pred_(__p) {}
-
-    template <typename _ForwardIterator2>
-    _LIBCPP_INLINE_VISIBILITY
-    pair<_ForwardIterator2, _ForwardIterator2>
-    operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const
-    {
-        return _VSTD::__search(__f, __l, __first_, __last_, __pred_,
-            typename iterator_traits<_ForwardIterator>::iterator_category(),
-            typename iterator_traits<_ForwardIterator2>::iterator_category());
-    }
-
-private:
-    _ForwardIterator __first_;
-    _ForwardIterator __last_;
-    _BinaryPredicate __pred_;
-    };
-
-template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
-_LIBCPP_INLINE_VISIBILITY
-default_searcher<_ForwardIterator, _BinaryPredicate>
-make_default_searcher( _ForwardIterator __f, _ForwardIterator __l, _BinaryPredicate __p = _BinaryPredicate ())
-{
-    return default_searcher<_ForwardIterator, _BinaryPredicate>(__f, __l, __p);
-}
-
 template<class _Key, class _Value, class _Hash, class _BinaryPredicate, bool /*useArray*/> class _BMSkipTable;
 
 //  General case for BM data searching; use a map
 template<class _Key, typename _Value, class _Hash, class _BinaryPredicate>
 class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, false> {
     typedef _Value value_type;
     typedef _Key   key_type;
 
     const _Value __default_value_;

libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11
-
-// <functional>
-
-// default searcher
-// template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
-// class default_searcher {
-// public:
-//     default_searcher(_ForwardIterator __f, _ForwardIterator __l,
-//                             _BinaryPredicate __p = _BinaryPredicate())
-//         : __first_(__f), __last_(__l), __pred_(__p) {}
-//
-//     template <typename _ForwardIterator2>
-//     pair<_ForwardIterator2, _ForwardIterator2>
-//     operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const {
-//         return std::search(__f, __l, __first_, __last_, __pred_);
-//         }
-//
-// private:
-//     _ForwardIterator __first_;
-//     _ForwardIterator __last_;
-//     _BinaryPredicate __pred_;
-//     };
-
-
-#include <experimental/algorithm>
-#include <experimental/functional>
-#include <cassert>
-
-#include "test_macros.h"
-#include "test_iterators.h"
-
-template <typename Iter1, typename Iter2>
-void do_search(Iter1 b1, Iter1 e1, Iter2 b2, Iter2 e2, Iter1 result) {
-    std::experimental::default_searcher<Iter2> s{b2, e2};
-    assert(result == std::experimental::search(b1, e1, s));
-}
-
-template <class Iter1, class Iter2>
-void
-test()
-{
-    int ia[] = {0, 1, 2, 3, 4, 5};
-    const unsigned sa = sizeof(ia)/sizeof(ia[0]);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia),    Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+1),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+1),    Iter2(ia+2),  Iter1(ia+1));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+2),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2));
-    do_search(Iter1(ia), Iter1(ia),      Iter2(ia+2),    Iter2(ia+3),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-1), Iter2(ia+sa), Iter1(ia+sa-1));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-3), Iter2(ia+sa), Iter1(ia+sa-3));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+sa), Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa-1), Iter2(ia),      Iter2(ia+sa), Iter1(ia+sa-1));
-    do_search(Iter1(ia), Iter1(ia+1),    Iter2(ia),      Iter2(ia+sa), Iter1(ia+1));
-    int ib[] = {0, 1, 2, 0, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sb = sizeof(ib)/sizeof(ib[0]);
-    int ic[] = {1};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ic), Iter2(ic+1), Iter1(ib+1));
-    int id[] = {1, 2};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(id), Iter2(id+2), Iter1(ib+1));
-    int ie[] = {1, 2, 3};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ie), Iter2(ie+3), Iter1(ib+4));
-    int ig[] = {1, 2, 3, 4};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ig), Iter2(ig+4), Iter1(ib+8));
-    int ih[] = {0, 1, 1, 1, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sh = sizeof(ih)/sizeof(ih[0]);
-    int ii[] = {1, 1, 2};
-    do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3));
-    int ij[] = {0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0};
-    const unsigned sj = sizeof(ij)/sizeof(ij[0]);
-    int ik[] = {0, 0, 0, 0, 1, 1, 1, 1, 0, 0};
-    const unsigned sk = sizeof(ik)/sizeof(ik[0]);
-    do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
-}
-
-int main(int, char**) {
-    test<forward_iterator<const int*>, forward_iterator<const int*> >();
-    test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<forward_iterator<const int*>, random_access_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
-    test<random_access_iterator<const int*>, forward_iterator<const int*> >();
-    test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
-
-  return 0;
-}

libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pred.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// <functional>
-
-// UNSUPPORTED: c++03, c++11
-
-// default searcher
-// template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
-// class default_searcher {
-// public:
-//     default_searcher(_ForwardIterator __f, _ForwardIterator __l,
-//                             _BinaryPredicate __p = _BinaryPredicate())
-//         : __first_(__f), __last_(__l), __pred_(__p) {}
-//
-//     template <typename _ForwardIterator2>
-//     pair<_ForwardIterator2, _ForwardIterator2>
-//     operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const {
-//         return std::search(__f, __l, __first_, __last_, __pred_);
-//         }
-//
-// private:
-//     _ForwardIterator __first_;
-//     _ForwardIterator __last_;
-//     _BinaryPredicate __pred_;
-//     };
-
-
-#include <experimental/algorithm>
-#include <experimental/functional>
-#include <cassert>
-
-#include "test_macros.h"
-#include "test_iterators.h"
-
-struct count_equal
-{
-    static unsigned count;
-    template <class T>
-    bool operator()(const T& x, const T& y) const
-        {++count; return x == y;}
-};
-
-unsigned count_equal::count = 0;
-
-template <typename Iter1, typename Iter2>
-void do_search(Iter1 b1, Iter1 e1, Iter2 b2, Iter2 e2, Iter1 result, unsigned max_count) {
-    std::experimental::default_searcher<Iter2, count_equal> s{b2, e2};
-    count_equal::count = 0;
-    assert(result == std::experimental::search(b1, e1, s));
-    assert(count_equal::count <= max_count);
-}
-
-template <class Iter1, class Iter2>
-void
-test()
-{
-    int ia[] = {0, 1, 2, 3, 4, 5};
-    const unsigned sa = sizeof(ia)/sizeof(ia[0]);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia),    Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+1),  Iter1(ia),      sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+1),    Iter2(ia+2),  Iter1(ia+1),    sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+2),  Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2),    sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2),    sa);
-    do_search(Iter1(ia), Iter1(ia),      Iter2(ia+2),    Iter2(ia+3),  Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-1), Iter2(ia+sa), Iter1(ia+sa-1), sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-3), Iter2(ia+sa), Iter1(ia+sa-3), 3*sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+sa), Iter1(ia),      sa*sa);
-    do_search(Iter1(ia), Iter1(ia+sa-1), Iter2(ia),      Iter2(ia+sa), Iter1(ia+sa-1), (sa-1)*sa);
-    do_search(Iter1(ia), Iter1(ia+1),    Iter2(ia),      Iter2(ia+sa), Iter1(ia+1),    sa);
-    int ib[] = {0, 1, 2, 0, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sb = sizeof(ib)/sizeof(ib[0]);
-    int ic[] = {1};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ic), Iter2(ic+1), Iter1(ib+1), sb);
-    int id[] = {1, 2};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(id), Iter2(id+2), Iter1(ib+1), sb*2);
-    int ie[] = {1, 2, 3};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ie), Iter2(ie+3), Iter1(ib+4), sb*3);
-    int ig[] = {1, 2, 3, 4};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ig), Iter2(ig+4), Iter1(ib+8), sb*4);
-    int ih[] = {0, 1, 1, 1, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sh = sizeof(ih)/sizeof(ih[0]);
-    int ii[] = {1, 1, 2};
-    do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
-}
-
-int main(int, char**) {
-    test<forward_iterator<const int*>, forward_iterator<const int*> >();
-    test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<forward_iterator<const int*>, random_access_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
-    test<random_access_iterator<const int*>, forward_iterator<const int*> >();
-    test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
-
-  return 0;
-}

libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11
-
-// <functional>
-
-// template<class ForwardIterator, class BinaryPredicate = equal_to<>>
-// default_searcher<ForwardIterator, BinaryPredicate>
-// make_default_searcher(ForwardIterator pat_first, ForwardIterator pat_last,
-//                       BinaryPredicate pred = BinaryPredicate());
-
-
-#include <experimental/algorithm>
-#include <experimental/functional>
-#include <cassert>
-
-#include "test_macros.h"
-#include "test_iterators.h"
-
-template <typename Iter1, typename Iter2>
-void do_search(Iter1 b1, Iter1 e1, Iter2 b2, Iter2 e2, Iter1 result) {
-    assert(result == std::experimental::search(b1, e1,
-        std::experimental::make_default_searcher(b2, e2)));
-}
-
-template <class Iter1, class Iter2>
-void
-test()
-{
-    int ia[] = {0, 1, 2, 3, 4, 5};
-    const unsigned sa = sizeof(ia)/sizeof(ia[0]);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia),     Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+1),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+1),    Iter2(ia+2),  Iter1(ia+1));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+2),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2));
-    do_search(Iter1(ia), Iter1(ia),      Iter2(ia+2),    Iter2(ia+3),  Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-1), Iter2(ia+sa), Iter1(ia+sa-1));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-3), Iter2(ia+sa), Iter1(ia+sa-3));
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+sa), Iter1(ia));
-    do_search(Iter1(ia), Iter1(ia+sa-1), Iter2(ia),      Iter2(ia+sa), Iter1(ia+sa-1));
-    do_search(Iter1(ia), Iter1(ia+1),    Iter2(ia),      Iter2(ia+sa), Iter1(ia+1));
-    int ib[] = {0, 1, 2, 0, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sb = sizeof(ib)/sizeof(ib[0]);
-    int ic[] = {1};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ic), Iter2(ic+1), Iter1(ib+1));
-    int id[] = {1, 2};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(id), Iter2(id+2), Iter1(ib+1));
-    int ie[] = {1, 2, 3};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ie), Iter2(ie+3), Iter1(ib+4));
-    int ig[] = {1, 2, 3, 4};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ig), Iter2(ig+4), Iter1(ib+8));
-    int ih[] = {0, 1, 1, 1, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sh = sizeof(ih)/sizeof(ih[0]);
-    int ii[] = {1, 1, 2};
-    do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3));
-    int ij[] = {0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0};
-    const unsigned sj = sizeof(ij)/sizeof(ij[0]);
-    int ik[] = {0, 0, 0, 0, 1, 1, 1, 1, 0, 0};
-    const unsigned sk = sizeof(ik)/sizeof(ik[0]);
-    do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
-}
-
-int main(int, char**) {
-    test<forward_iterator<const int*>, forward_iterator<const int*> >();
-    test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<forward_iterator<const int*>, random_access_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
-    test<random_access_iterator<const int*>, forward_iterator<const int*> >();
-    test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
-
-  return 0;
-}

libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pred.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03, c++11
-
-// <functional>
-
-// template<class ForwardIterator, class BinaryPredicate = equal_to<>>
-// default_searcher<ForwardIterator, BinaryPredicate>
-// make_default_searcher(ForwardIterator pat_first, ForwardIterator pat_last,
-//                       BinaryPredicate pred = BinaryPredicate());
-
-
-#include <experimental/algorithm>
-#include <experimental/functional>
-#include <cassert>
-
-#include "test_macros.h"
-#include "test_iterators.h"
-
-struct count_equal
-{
-    static unsigned count;
-    template <class T>
-    bool operator()(const T& x, const T& y)
-        {++count; return x == y;}
-};
-
-unsigned count_equal::count = 0;
-
-template <typename Iter1, typename Iter2>
-void do_search(Iter1 b1, Iter1 e1, Iter2 b2, Iter2 e2, Iter1 result, unsigned max_count) {
-    count_equal::count = 0;
-    assert(result == std::experimental::search(b1, e1,
-        std::experimental::make_default_searcher(b2, e2)));
-    assert(count_equal::count <= max_count);
-}
-
-template <class Iter1, class Iter2>
-void
-test()
-{
-    int ia[] = {0, 1, 2, 3, 4, 5};
-    const unsigned sa = sizeof(ia)/sizeof(ia[0]);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia),    Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+1),  Iter1(ia),      sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+1),    Iter2(ia+2),  Iter1(ia+1),    sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+2),  Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2),    sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+2),    Iter2(ia+3),  Iter1(ia+2),    sa);
-    do_search(Iter1(ia), Iter1(ia),      Iter2(ia+2),    Iter2(ia+3),  Iter1(ia),      0);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-1), Iter2(ia+sa), Iter1(ia+sa-1), sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia+sa-3), Iter2(ia+sa), Iter1(ia+sa-3), 3*sa);
-    do_search(Iter1(ia), Iter1(ia+sa),   Iter2(ia),      Iter2(ia+sa), Iter1(ia),      sa*sa);
-    do_search(Iter1(ia), Iter1(ia+sa-1), Iter2(ia),      Iter2(ia+sa), Iter1(ia+sa-1), (sa-1)*sa);
-    do_search(Iter1(ia), Iter1(ia+1),    Iter2(ia),      Iter2(ia+sa), Iter1(ia+1),    sa);
-    int ib[] = {0, 1, 2, 0, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sb = sizeof(ib)/sizeof(ib[0]);
-    int ic[] = {1};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ic), Iter2(ic+1), Iter1(ib+1), sb);
-    int id[] = {1, 2};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(id), Iter2(id+2), Iter1(ib+1), sb*2);
-    int ie[] = {1, 2, 3};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ie), Iter2(ie+3), Iter1(ib+4), sb*3);
-    int ig[] = {1, 2, 3, 4};
-    do_search(Iter1(ib), Iter1(ib+sb), Iter2(ig), Iter2(ig+4), Iter1(ib+8), sb*4);
-    int ih[] = {0, 1, 1, 1, 1, 2, 3, 0, 1, 2, 3, 4};
-    const unsigned sh = sizeof(ih)/sizeof(ih[0]);
-    int ii[] = {1, 1, 2};
-    do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
-}
-
-int main(int, char**) {
-    test<forward_iterator<const int*>, forward_iterator<const int*> >();
-    test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<forward_iterator<const int*>, random_access_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, forward_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<bidirectional_iterator<const int*>, random_access_iterator<const int*> >();
-    test<random_access_iterator<const int*>, forward_iterator<const int*> >();
-    test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
-    test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
-
-  return 0;
-}