kicad/thirdparty/pegtl/pegtl/change_action_and_state.hpp

73 lines
2.5 KiB
C++

// Copyright (c) 2019-2021 Dr. Colin Hirsch and Daniel Frey
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
#ifndef TAO_PEGTL_CHANGE_ACTION_AND_STATE_HPP
#define TAO_PEGTL_CHANGE_ACTION_AND_STATE_HPP
#include <type_traits>
#include "apply_mode.hpp"
#include "config.hpp"
#include "match.hpp"
#include "nothing.hpp"
#include "rewind_mode.hpp"
#include "internal/dependent_false.hpp"
namespace TAO_PEGTL_NAMESPACE
{
template< template< typename... > class NewAction, typename NewState >
struct change_action_and_state
: maybe_nothing
{
template< typename Rule,
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 )
{
static_assert( !std::is_same_v< Action< void >, NewAction< void > >, "old and new action class templates are identical" );
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, NewAction, Control >( in, s ) ) {
if constexpr( A == apply_mode::action ) {
Action< Rule >::success( static_cast< const ParseInput& >( in ), s, st... );
}
return true;
}
return false;
}
else if constexpr( std::is_default_constructible_v< NewState > ) {
NewState s;
if( Control< Rule >::template match< A, M, NewAction, Control >( in, s ) ) {
if constexpr( A == apply_mode::action ) {
Action< Rule >::success( static_cast< const ParseInput& >( in ), s, st... );
}
return true;
}
return false;
}
else {
static_assert( internal::dependent_false< NewState >, "unable to instantiate new state" );
}
}
template< typename ParseInput,
typename... States >
static void success( const ParseInput& in, NewState& s, States&&... st ) noexcept( noexcept( s.success( in, st... ) ) )
{
s.success( in, st... );
}
};
} // namespace TAO_PEGTL_NAMESPACE
#endif