# C++ GLR skeleton for Bison # Copyright (C) 2002-2015 Free Software Foundation, Inc. # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. # This skeleton produces a C++ class that encapsulates a C glr parser. # This is in order to reduce the maintenance burden. The glr.c # skeleton is clean and pure enough so that there are no real # problems. The C++ interface is the same as that of lalr1.cc. In # fact, glr.c can replace yacc.c without the user noticing any # difference, and similarly for glr.cc replacing lalr1.cc. # # The passing of parse-params # # The additional arguments are stored as members of the parser # object, yyparser. The C routines need to carry yyparser # throughout the C parser; that's easy: make yyparser an # additional parse-param. But because the C++ skeleton needs to # know the "real" original parse-param, we save them # (b4_parse_param_orig). Note that b4_parse_param is overquoted # (and c.m4 strips one level of quotes). This is a PITA, and # explains why there are so many levels of quotes. # # The locations # # We use location.cc just like lalr1.cc, but because glr.c stores # the locations in a union, the position and location classes # must not have a constructor. Therefore, contrary to lalr1.cc, we # must not define "b4_location_constructors". As a consequence the # user must initialize the first positions (in particular the # filename member). # We require a pure interface. m4_define([b4_pure_flag], [1]) m4_include(b4_pkgdatadir/[c++.m4]) b4_bison_locations_if([m4_include(b4_pkgdatadir/[location.cc])]) m4_define([b4_parser_class_name], [b4_percent_define_get([[parser_class_name]])]) # Save the parse parameters. m4_define([b4_parse_param_orig], m4_defn([b4_parse_param])) # b4_parse_param_wrap # ------------------- # New ones. m4_ifset([b4_parse_param], [m4_define([b4_parse_param_wrap], [[b4_namespace_ref::b4_parser_class_name[& yyparser], [[yyparser]]],] m4_defn([b4_parse_param]))], [m4_define([b4_parse_param_wrap], [[b4_namespace_ref::b4_parser_class_name[& yyparser], [[yyparser]]]]) ]) # b4_yy_symbol_print_define # ------------------------- # Bypass the default implementation to generate the "yy_symbol_print" # and "yy_symbol_value_print" functions. m4_define([b4_yy_symbol_print_define], [[ /*--------------------. | Print this symbol. | `--------------------*/ ]b4_function_define([yy_symbol_print], [static void], [[FILE *], []], [[int yytype], [yytype]], [[const ]b4_namespace_ref::b4_parser_class_name[::semantic_type *yyvaluep], [yyvaluep]][]dnl b4_locations_if([, [[const ]b4_namespace_ref::b4_parser_class_name[::location_type *yylocationp], [yylocationp]]]), b4_parse_param)[ { ]b4_parse_param_use[]dnl [ yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[); } ]])[ # Hijack the initial action to initialize the locations. ]b4_bison_locations_if([m4_define([b4_initial_action], [yylloc.initialize ();]m4_ifdef([b4_initial_action], [ m4_defn([b4_initial_action])]))])[ # Hijack the post prologue to insert early definition of YYLLOC_DEFAULT # and declaration of yyerror. ]m4_append([b4_post_prologue], [b4_syncline([@oline@], [@ofile@])[ ]b4_yylloc_default_define[ #define YYRHSLOC(Rhs, K) ((Rhs)[K].yystate.yyloc) ]b4_function_declare([yyerror], [static void],b4_locations_if([ [[const ]b4_namespace_ref::b4_parser_class_name[::location_type *yylocationp], [yylocationp]],]) b4_parse_param, [[const char* msg], [msg]])]) #undef yynerrs #undef yychar #undef yylval]b4_locations_if([ #undef yylloc]) m4_if(b4_prefix, [yy], [], [[/* Substitute the variable and function names. */ #define yyparse ]b4_prefix[parse #define yylex ]b4_prefix[lex #define yyerror ]b4_prefix[error #define yydebug ]b4_prefix[debug ]]b4_pure_if([], [[ #define yylval ]b4_prefix[lval #define yychar ]b4_prefix[char #define yynerrs ]b4_prefix[nerrs]b4_locations_if([[ #define yylloc ]b4_prefix[lloc]])])) # Hijack the epilogue to define implementations (yyerror, parser member # functions etc.). m4_append([b4_epilogue], [b4_syncline([@oline@], [@ofile@])[ /*------------------. | Report an error. | `------------------*/ ]b4_function_define([yyerror], [static void],b4_locations_if([ [[const ]b4_namespace_ref::b4_parser_class_name[::location_type *yylocationp], [yylocationp]],]) b4_parse_param, [[const char* msg], [msg]])[ { ]b4_parse_param_use[]dnl [ yyparser.error (]b4_locations_if([[*yylocationp, ]])[msg); } ]b4_namespace_open[ ]dnl In this section, the parse params are the original parse_params. m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl [ /// Build a parser object. ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [ :])[ #if ]b4_api_PREFIX[DEBUG ]m4_ifset([b4_parse_param], [ ], [ :])[yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[ #endif]b4_parse_param_cons[ { } ]b4_parser_class_name::~b4_parser_class_name[ () { } int ]b4_parser_class_name[::parse () { return ::yyparse (*this]b4_user_args[); } #if ]b4_api_PREFIX[DEBUG /*--------------------. | Print this symbol. | `--------------------*/ inline void ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype, const semantic_type* yyvaluep]b4_locations_if([[, const location_type* yylocationp]])[) {]b4_locations_if([[ YYUSE (yylocationp);]])[ YYUSE (yyvaluep); std::ostream& yyoutput = debug_stream (); std::ostream& yyo = yyoutput; YYUSE (yyo); ]b4_symbol_actions([printer])[ } void ]b4_parser_class_name[::yy_symbol_print_ (int yytype, const semantic_type* yyvaluep]b4_locations_if([[, const location_type* yylocationp]])[) { *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm") << ' ' << yytname[yytype] << " ("]b4_locations_if([[ << *yylocationp << ": "]])[; yy_symbol_value_print_ (yytype, yyvaluep]b4_locations_if([[, yylocationp]])[); *yycdebug_ << ')'; } std::ostream& ]b4_parser_class_name[::debug_stream () const { return *yycdebug_; } void ]b4_parser_class_name[::set_debug_stream (std::ostream& o) { yycdebug_ = &o; } ]b4_parser_class_name[::debug_level_type ]b4_parser_class_name[::debug_level () const { return yydebug; } void ]b4_parser_class_name[::set_debug_level (debug_level_type l) { // Actually, it is yydebug which is really used. yydebug = l; } #endif ]m4_popdef([b4_parse_param])dnl b4_namespace_close ]) # b4_shared_declarations # ---------------------- # Declaration that might either go into the header (if --defines) # or open coded in the parser body. m4_define([b4_shared_declarations], [m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl b4_percent_code_get([[requires]])[ #include <stdexcept> #include <string> #include <iostream>]b4_defines_if([ b4_bison_locations_if([[#include "location.hh"]])])[ ]b4_YYDEBUG_define[ ]b4_namespace_open[ ]b4_defines_if([], [b4_bison_locations_if([b4_position_define b4_location_define])])[ /// A Bison parser. class ]b4_parser_class_name[ { public: ]b4_public_types_declare[ /// Build a parser object. ]b4_parser_class_name[ (]b4_parse_param_decl[); virtual ~]b4_parser_class_name[ (); /// Parse. /// \returns 0 iff parsing succeeded. virtual int parse (); /// The current debugging stream. std::ostream& debug_stream () const; /// Set the current debugging stream. void set_debug_stream (std::ostream &); /// Type for debugging levels. typedef int debug_level_type; /// The current debugging level. debug_level_type debug_level () const; /// Set the current debugging level. void set_debug_level (debug_level_type l); public: /// Report a syntax error.]b4_locations_if([[ /// \param loc where the syntax error is found.]])[ /// \param msg a description of the syntax error. virtual void error (]b4_locations_if([[const location_type& loc, ]])[const std::string& msg); # if ]b4_api_PREFIX[DEBUG public: /// \brief Report a symbol value on the debug stream. /// \param yytype The token type. /// \param yyvaluep Its semantic value.]b4_locations_if([[ /// \param yylocationp Its location.]])[ virtual void yy_symbol_value_print_ (int yytype, const semantic_type* yyvaluep]b4_locations_if([[, const location_type* yylocationp]])[); /// \brief Report a symbol on the debug stream. /// \param yytype The token type. /// \param yyvaluep Its semantic value.]b4_locations_if([[ /// \param yylocationp Its location.]])[ virtual void yy_symbol_print_ (int yytype, const semantic_type* yyvaluep]b4_locations_if([[, const location_type* yylocationp]])[); private: // Debugging. std::ostream* yycdebug_; #endif ]b4_parse_param_vars[ }; ]dnl Redirections for glr.c. b4_percent_define_flag_if([[global_tokens_and_yystype]], [b4_token_defines]) [ #ifndef ]b4_api_PREFIX[STYPE # define ]b4_api_PREFIX[STYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type #endif #ifndef ]b4_api_PREFIX[LTYPE # define ]b4_api_PREFIX[LTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type #endif ]b4_namespace_close[ ]b4_percent_code_get([[provides]])[ ]m4_popdef([b4_parse_param])dnl ]) b4_defines_if( [b4_output_begin([b4_spec_defines_file]) b4_copyright([Skeleton interface for Bison GLR parsers in C++], [2002-2015])[ // C++ GLR parser skeleton written by Akim Demaille. ]b4_cpp_guard_open([b4_spec_defines_file])[ ]b4_shared_declarations[ ]b4_cpp_guard_close([b4_spec_defines_file])[ ]b4_output_end()]) # Let glr.c (and b4_shared_declarations) believe that the user # arguments include the parser itself. m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_wrap])) m4_include(b4_pkgdatadir/[glr.c]) m4_popdef([b4_parse_param])

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