geode/codegen/Broma/PEGTL-3.2.7/include/tao/pegtl/internal/state.hpp

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2022-07-30 12:24:03 -04:00
// Copyright (c) 2014-2022 Dr. Colin Hirsch and Daniel Frey
// Please see LICENSE for license or visit https://github.com/taocpp/PEGTL/
#ifndef TAO_PEGTL_INTERNAL_STATE_HPP
#define TAO_PEGTL_INTERNAL_STATE_HPP
#include "../config.hpp"
#include <type_traits>
#include "dependent_false.hpp"
#include "enable_control.hpp"
#include "seq.hpp"
#include "success.hpp"
#include "../apply_mode.hpp"
#include "../rewind_mode.hpp"
#include "../type_list.hpp"
namespace TAO_PEGTL_NAMESPACE::internal
{
template< typename NewState, typename... Rules >
struct state
: state< NewState, seq< Rules... > >
{};
template< typename NewState >
struct state< NewState >
: success
{};
template< typename NewState, typename Rule >
struct state< NewState, Rule >
{
using rule_t = state;
using subs_t = type_list< Rule >;
template< apply_mode A,
rewind_mode M,
template< typename... >
class Action,
template< typename... >
class Control,
typename ParseInput,
typename... States >
[[nodiscard]] static bool match( ParseInput& in, States&&... st )
{
if constexpr( std::is_constructible_v< NewState, const ParseInput&, States... > ) {
NewState s( static_cast< const ParseInput& >( in ), st... );
if( Control< Rule >::template match< A, M, Action, Control >( in, s ) ) {
s.success( static_cast< const ParseInput& >( in ), st... );
return true;
}
return false;
}
else if constexpr( std::is_default_constructible_v< NewState > ) {
NewState s;
if( Control< Rule >::template match< A, M, Action, Control >( in, s ) ) {
s.success( static_cast< const ParseInput& >( in ), st... );
return true;
}
return false;
}
else {
static_assert( internal::dependent_false< NewState >, "unable to instantiate new state" );
}
}
};
template< typename NewState, typename... Rules >
inline constexpr bool enable_control< state< NewState, Rules... > > = false;
} // namespace TAO_PEGTL_NAMESPACE::internal
#endif