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-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
10#define _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
11
12#include <__config>
13
14#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
15# pragma GCC system_header
16#endif
17
18_LIBCPP_BEGIN_NAMESPACE_STD
19
20template <bool, class _Tp = void> struct _LIBCPP_TEMPLATE_VIS enable_if {};
21template <class _Tp> struct _LIBCPP_TEMPLATE_VIS enable_if<true, _Tp> {typedef _Tp type;};
22
23template <bool _Bp, class _Tp = void> using __enable_if_t _LIBCPP_NODEBUG = typename enable_if<_Bp, _Tp>::type;
24
25#if _LIBCPP_STD_VER > 11
26template <bool _Bp, class _Tp = void> using enable_if_t = typename enable_if<_Bp, _Tp>::type;
27#endif
28
29_LIBCPP_END_NAMESPACE_STD
30
31#endif // _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
32

source code of flutter_engine/third_party/libcxx/include/__type_traits/enable_if.h