// 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_MUST_HPP #define TAO_PEGTL_INTERNAL_MUST_HPP #if !defined( __cpp_exceptions ) #error "Exception support required for tao/pegtl/internal/must.hpp" #else #include "../config.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 { // The general case applies must<> to each of the // rules in the 'Rules' parameter pack individually. template< typename... Rules > struct must : seq< must< Rules >... > {}; template<> struct must<> : success {}; // While in theory the implementation for a single rule could // be simplified to must< Rule > = sor< Rule, raise< Rule > >, this // would result in some unnecessary run-time overhead. template< typename Rule > struct must< Rule > { using rule_t = must; using subs_t = type_list< Rule >; template< apply_mode A, rewind_mode, template< typename... > class Action, template< typename... > class Control, typename ParseInput, typename... States > [[nodiscard]] static bool match( ParseInput& in, States&&... st ) { if( !Control< Rule >::template match< A, rewind_mode::dontcare, Action, Control >( in, st... ) ) { Control< Rule >::raise( static_cast< const ParseInput& >( in ), st... ); } return true; } }; template< typename... Rules > inline constexpr bool enable_control< must< Rules... > > = false; } // namespace TAO_PEGTL_NAMESPACE::internal #endif #endif