geode/codegen/Broma/PEGTL-3.2.7/include/tao/pegtl/contrib/if_then.hpp

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2022-07-30 12:24:03 -04:00
// Copyright (c) 2018-2022 Dr. Colin Hirsch and Daniel Frey
// Please see LICENSE for license or visit https://github.com/taocpp/PEGTL/
#ifndef TAO_PEGTL_CONTRIB_IF_THEN_HPP
#define TAO_PEGTL_CONTRIB_IF_THEN_HPP
#include <type_traits>
#include "../config.hpp"
#include "../internal/enable_control.hpp"
#include "../internal/failure.hpp"
#include "../internal/if_then_else.hpp"
#include "../internal/seq.hpp"
#include "../internal/success.hpp"
namespace TAO_PEGTL_NAMESPACE
{
namespace internal
{
template< typename Cond, typename Then >
struct if_pair
{};
template< typename... Pairs >
struct if_then;
template< typename Cond, typename Then, typename... Pairs >
struct if_then< if_pair< Cond, Then >, Pairs... >
: if_then_else< Cond, Then, if_then< Pairs... > >
{
template< typename ElseCond, typename... Thens >
using else_if_then = if_then< if_pair< Cond, Then >, Pairs..., if_pair< ElseCond, seq< Thens... > > >;
template< typename... Thens >
using else_then = if_then_else< Cond, Then, if_then< Pairs..., if_pair< success, seq< Thens... > > > >;
};
template<>
struct if_then<>
: failure
{};
template< typename... Pairs >
inline constexpr bool enable_control< if_then< Pairs... > > = false;
} // namespace internal
template< typename Cond, typename... Thens >
struct if_then
: internal::if_then< internal::if_pair< Cond, internal::seq< Thens... > > >
{};
} // namespace TAO_PEGTL_NAMESPACE
#endif