| # D skeleton for Bison -*- autoconf -*- |
| |
| # Copyright (C) 2007-2012, 2019-2021 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 <https://www.gnu.org/licenses/>. |
| |
| m4_include(b4_skeletonsdir/[d.m4]) |
| |
| b4_header_if([b4_complain([%header/%defines does not make sense in D])]) |
| |
| # parse.lac |
| b4_percent_define_default([[parse.lac]], [[none]]) |
| b4_percent_define_check_values([[[[parse.lac]], [[full]], [[none]]]]) |
| b4_define_flag_if([lac]) |
| m4_define([b4_lac_flag], |
| [m4_if(b4_percent_define_get([[parse.lac]]), |
| [none], [[0]], [[1]])]) |
| |
| |
| ## --------------- ## |
| ## api.push-pull. ## |
| ## --------------- ## |
| |
| b4_percent_define_default([[api.push-pull]], [[pull]]) |
| b4_percent_define_check_values([[[[api.push-pull]], |
| [[pull]], [[push]], [[both]]]]) |
| |
| # Define m4 conditional macros that encode the value |
| # of the api.push-pull flag. |
| b4_define_flag_if([pull]) m4_define([b4_pull_flag], [[1]]) |
| b4_define_flag_if([push]) m4_define([b4_push_flag], [[1]]) |
| m4_case(b4_percent_define_get([[api.push-pull]]), |
| [pull], [m4_define([b4_push_flag], [[0]])], |
| [push], [m4_define([b4_pull_flag], [[0]])]) |
| |
| # Define a macro to be true when api.push-pull has the value "both". |
| m4_define([b4_both_if],[b4_push_if([b4_pull_if([$1],[$2])],[$2])]) |
| |
| # Handle BISON_USE_PUSH_FOR_PULL for the test suite. So that push parsing |
| # tests function as written, do not let BISON_USE_PUSH_FOR_PULL modify the |
| # behavior of Bison at all when push parsing is already requested. |
| b4_define_flag_if([use_push_for_pull]) |
| b4_use_push_for_pull_if([ |
| b4_push_if([m4_define([b4_use_push_for_pull_flag], [[0]])], |
| [m4_define([b4_push_flag], [[1]])])]) |
| |
| |
| # Define a macro to encapsulate the parse state variables. This |
| # allows them to be defined either in parse() when doing pull parsing, |
| # or as class instance variable when doing push parsing. |
| b4_output_begin([b4_parser_file_name]) |
| b4_copyright([Skeleton implementation for Bison LALR(1) parsers in D], |
| [2007-2012, 2019-2021])[ |
| ]b4_disclaimer[ |
| ]b4_percent_define_ifdef([package], [module b4_percent_define_get([package]); |
| ])[ |
| version(D_Version2) { |
| } else { |
| static assert(false, "need compiler for D Version 2"); |
| } |
| |
| ]b4_user_pre_prologue[ |
| ]b4_user_post_prologue[ |
| ]b4_percent_code_get([[imports]])[ |
| import std.format; |
| import std.conv; |
| |
| /** |
| * Handle error message internationalisation. |
| */ |
| static if (!is(typeof(YY_))) { |
| version(YYENABLE_NLS) |
| { |
| version(ENABLE_NLS) |
| { |
| extern(C) char* dgettext(const char*, const char*); |
| string YY_(const char* s) |
| { |
| return to!string(dgettext("bison-runtime", s)); |
| } |
| } |
| } |
| static if (!is(typeof(YY_))) |
| { |
| pragma(inline, true) |
| string YY_(string msg) { return msg; } |
| } |
| } |
| |
| /** |
| * A Bison parser, automatically generated from <tt>]m4_bpatsubst(b4_file_name, [^"\(.*\)"$], [\1])[</tt>. |
| * |
| * @@author LALR (1) parser skeleton written by Paolo Bonzini. |
| * Port to D language was done by Oliver Mangold. |
| */ |
| |
| /** |
| * Communication interface between the scanner and the Bison-generated |
| * parser <tt>]b4_parser_class[</tt>. |
| */ |
| public interface Lexer |
| { |
| /** |
| * Entry point for the scanner. Returns the token identifier corresponding |
| * to the next token and prepares to return the semantic value |
| * ]b4_locations_if([and beginning/ending positions ])[of the token. |
| * @@return the token identifier corresponding to the next token. */ |
| Symbol yylex (); |
| |
| /** |
| * Entry point for error reporting. Emits an error |
| * ]b4_locations_if([referring to the given location ])[in a user-defined way. |
| *]b4_locations_if([[ |
| * @@param loc The location of the element to which the |
| * error message is related]])[ |
| * @@param s The string for the error message. */ |
| void yyerror (]b4_locations_if([[const Location loc, ]])[string s); |
| ]b4_parse_error_bmatch([custom], [[ |
| /** |
| * Build and emit a "syntax error" message in a user-defined way. |
| * |
| * @@param ctx The context of the error. |
| */ |
| void reportSyntaxError(]b4_parser_class[.Context ctx); |
| ]])[ |
| } |
| |
| ]b4_public_types_declare[ |
| |
| ]b4_locations_if([b4_position_type_if([[ |
| static assert(__traits(compiles, |
| (new Position[1])[0]=(new Position[1])[0]), |
| "struct/class Position must be default-constructible " |
| "and assignable"); |
| static assert(__traits(compiles, (new string[1])[0]=(new Position).toString()), |
| "error: struct/class Position must have toString method"); |
| ]], [[ |
| /** |
| * A struct denoting a point in the input.*/ |
| public struct ]b4_position_type[ { |
| |
| /** The column index within the line of input. */ |
| public int column = 1; |
| /** The line number within an input file. */ |
| public int line = 1; |
| /** The name of the input file. */ |
| public string filename = null; |
| |
| /** |
| * A string representation of the position. */ |
| public string toString() const { |
| if (filename) |
| return format("%s:%d.%d", filename, line, column); |
| else |
| return format("%d.%d", line, column); |
| } |
| } |
| ]])b4_location_type_if([[ |
| static assert(__traits(compiles, (new Location((new Position[1])[0]))) && |
| __traits(compiles, (new Location((new Position[1])[0], (new Position[1])[0]))), |
| "error: struct/class Location must have " |
| "default constructor and constructors this(Position) and this(Position, Position)."); |
| static assert(__traits(compiles, (new Location[1])[0].begin=(new Location[1])[0].begin) && |
| __traits(compiles, (new Location[1])[0].begin=(new Location[1])[0].end) && |
| __traits(compiles, (new Location[1])[0].end=(new Location[1])[0].begin) && |
| __traits(compiles, (new Location[1])[0].end=(new Location[1])[0].end), |
| "error: struct/class Location must have assignment-compatible " |
| "members/properties 'begin' and 'end'."); |
| static assert(__traits(compiles, (new string[1])[0]=(new Location[1])[0].toString()), |
| "error: struct/class Location must have toString method."); |
| |
| private immutable bool yy_location_is_class = !__traits(compiles, *(new Location((new Position[1])[0])));]], [[ |
| /** |
| * A struct defining a pair of positions. Positions, defined by the |
| * <code>Position</code> struct, denote a point in the input. |
| * Locations represent a part of the input through the beginning |
| * and ending positions. */ |
| public struct ]b4_location_type[ |
| { |
| /** The first, inclusive, position in the range. */ |
| public Position begin; |
| |
| /** The first position beyond the range. */ |
| public Position end; |
| |
| /** |
| * Create a <code>Location</code> denoting an empty range located at |
| * a given point. |
| * @@param loc The position at which the range is anchored. */ |
| public this(Position loc) |
| { |
| this.begin = this.end = loc; |
| } |
| |
| /** |
| * Create a <code>Location</code> from the endpoints of the range. |
| * @@param begin The first position included in the range. |
| * @@param end The first position beyond the range. */ |
| public this(Position begin, Position end) |
| { |
| this.begin = begin; |
| this.end = end; |
| } |
| |
| /** |
| * Reset initial location to final location. |
| */ |
| public void step() |
| { |
| this.begin = this.end; |
| } |
| |
| /** |
| * A representation of the location. |
| */ |
| public string toString() const |
| { |
| auto end_col = 0 < end.column ? end.column - 1 : 0; |
| auto res = begin.toString (); |
| if (end.filename && begin.filename != end.filename) |
| res ~= "-" ~ format("%s:%d.%d", end.filename, end.line, end_col); |
| else if (begin.line < end.line) |
| res ~= "-" ~ format("%d.%d", end.line, end_col); |
| else if (begin.column < end_col) |
| res ~= "-" ~ format("%d", end_col); |
| return res; |
| } |
| } |
| |
| private immutable bool yy_location_is_class = false; |
| |
| ]])])[]b4_value_type_setup[]m4_ifdef([b4_user_union_members], [private union YYSemanticType |
| { |
| b4_user_union_members |
| };], |
| [m4_if(b4_tag_seen_flag, 0, |
| [[private alias int YYSemanticType;]])])[ |
| ]b4_token_enums[ |
| ]b4_parser_class_declaration[ |
| { |
| ]b4_identification[ |
| |
| ]b4_declare_symbol_enum[ |
| |
| ]b4_locations_if([[ |
| private final Location yylloc_from_stack (ref YYStack rhs, int n) |
| { |
| static if (yy_location_is_class) { |
| if (n > 0) |
| return new Location (rhs.locationAt (n-1).begin, rhs.locationAt (0).end); |
| else |
| return new Location (rhs.locationAt (0).end); |
| } else { |
| if (n > 0) |
| return Location (rhs.locationAt (n-1).begin, rhs.locationAt (0).end); |
| else |
| return Location (rhs.locationAt (0).end); |
| } |
| }]])[ |
| |
| ]b4_lexer_if([[ private class YYLexer implements Lexer { |
| ]b4_percent_code_get([[lexer]])[ |
| } |
| ]])[ |
| /** The object doing lexical analysis for us. */ |
| private Lexer yylexer; |
| |
| ]b4_parse_param_vars[ |
| |
| ]b4_lexer_if([[ |
| /** |
| * Instantiate the Bison-generated parser. |
| */ |
| public this] (b4_parse_param_decl([b4_lex_param_decl])[) { |
| ]b4_percent_code_get([[init]])[]b4_lac_if([[ |
| this.yylacStack = new int[]; |
| this.yylacEstablished = false;]])[ |
| this (new YYLexer(]b4_lex_param_call[)); |
| } |
| ]])[ |
| |
| /** |
| * Instantiate the Bison-generated parser. |
| * @@param yylexer The scanner that will supply tokens to the parser. |
| */ |
| ]b4_lexer_if([[protected]], [[public]]) [this (]b4_parse_param_decl([[Lexer yylexer]])[) { |
| this.yylexer = yylexer;]b4_parse_trace_if([[ |
| this.yyDebugStream = stderr;]])[ |
| ]b4_parse_param_cons[ |
| } |
| ]b4_parse_trace_if([[ |
| import std.stdio; |
| private File yyDebugStream; |
| |
| /** |
| * The <tt>File</tt> on which the debugging output is |
| * printed. |
| */ |
| public File getDebugStream () { return yyDebugStream; } |
| |
| /** |
| * Set the <tt>std.File</tt> on which the debug output is printed. |
| * @@param s The stream that is used for debugging output. |
| */ |
| public final void setDebugStream(File s) { yyDebugStream = s; } |
| |
| private int yydebug = 0; |
| |
| /** |
| * Answer the verbosity of the debugging output; 0 means that all kinds of |
| * output from the parser are suppressed. |
| */ |
| public final int getDebugLevel() { return yydebug; } |
| |
| /** |
| * Set the verbosity of the debugging output; 0 means that all kinds of |
| * output from the parser are suppressed. |
| * @@param level The verbosity level for debugging output. |
| */ |
| public final void setDebugLevel(int level) { yydebug = level; } |
| |
| protected final void yycdebug (string s) { |
| if (0 < yydebug) |
| yyDebugStream.write (s); |
| } |
| |
| protected final void yycdebugln (string s) { |
| if (0 < yydebug) |
| yyDebugStream.writeln (s); |
| } |
| ]])[ |
| private final ]b4_parser_class[.Symbol yylex () { |
| return yylexer.yylex (); |
| } |
| |
| protected final void yyerror (]b4_locations_if([[const Location loc, ]])[string s) { |
| yylexer.yyerror (]b4_locations_if([loc, ])[s); |
| } |
| |
| /** |
| * The number of syntax errors so far. |
| */ |
| public int numberOfErrors() const { return yynerrs_; } |
| private int yynerrs_ = 0; |
| |
| /** |
| * Returned by a Bison action in order to stop the parsing process and |
| * return success (<tt>true</tt>). */ |
| public static immutable int YYACCEPT = 0; |
| |
| /** |
| * Returned by a Bison action in order to stop the parsing process and |
| * return failure (<tt>false</tt>). */ |
| public static immutable int YYABORT = 1; |
| ]b4_push_if([ |
| /** |
| * Returned by a Bison action in order to request a new token. |
| */ |
| public static immutable int YYPUSH_MORE = 4;])[ |
| |
| /** |
| * Returned by a Bison action in order to start error recovery without |
| * printing an error message. */ |
| public static immutable int YYERROR = 2; |
| |
| // Internal return codes that are not supported for user semantic |
| // actions. |
| private static immutable int YYERRLAB = 3; |
| private static immutable int YYNEWSTATE = 4; |
| private static immutable int YYDEFAULT = 5; |
| private static immutable int YYREDUCE = 6; |
| private static immutable int YYERRLAB1 = 7; |
| private static immutable int YYRETURN = 8; |
| ]b4_push_if([[ private static immutable int YYGETTOKEN = 9; /* Signify that a new token is expected when doing push-parsing. */]])[ |
| |
| ]b4_locations_if([ |
| private static immutable YYSemanticType yy_semantic_null;])[ |
| private int yyerrstatus_ = 0; |
| |
| private void yyerrok() |
| { |
| yyerrstatus_ = 0; |
| } |
| |
| // Lookahead symbol kind. |
| SymbolKind yytoken = ]b4_symbol(empty, kind)[; |
| |
| /* State. */ |
| int yyn = 0; |
| int yylen = 0; |
| int yystate = 0; |
| |
| YYStack yystack; |
| |
| int label = YYNEWSTATE; |
| |
| /* Error handling. */ |
| ]b4_locations_if([[ |
| /// The location where the error started. |
| Location yyerrloc; |
| |
| /// Location of the lookahead. |
| Location yylloc; |
| |
| /// @@$. |
| Location yyloc;]])[ |
| |
| /// Semantic value of the lookahead. |
| Value yylval; |
| |
| /** |
| * Whether error recovery is being done. In this state, the parser |
| * reads token until it reaches a known state, and then restarts normal |
| * operation. */ |
| public final bool recovering () |
| { |
| return yyerrstatus_ == 0; |
| } |
| |
| /** Compute post-reduction state. |
| * @@param yystate the current state |
| * @@param yysym the nonterminal to push on the stack |
| */ |
| private int yyLRGotoState(int yystate, int yysym) { |
| int yyr = yypgoto_[yysym - yyntokens_] + yystate; |
| if (0 <= yyr && yyr <= yylast_ && yycheck_[yyr] == yystate) |
| return yytable_[yyr]; |
| else |
| return yydefgoto_[yysym - yyntokens_]; |
| } |
| |
| private int yyaction (int yyn, ref YYStack yystack, int yylen) |
| { |
| Value yyval;]b4_locations_if([[ |
| Location yyloc = yylloc_from_stack (yystack, yylen);]])[ |
| |
| /* If YYLEN is nonzero, implement the default value of the action: |
| `$$ = $1'. Otherwise, use the top of the stack. |
| |
| Otherwise, the following line sets YYVAL to garbage. |
| This behavior is undocumented and Bison |
| users should not rely upon it. */ |
| if (yylen > 0) |
| yyval = yystack.valueAt (yylen - 1); |
| else |
| yyval = yystack.valueAt (0); |
| |
| ]b4_parse_trace_if([[ |
| yy_reduce_print (yyn, yystack);]])[ |
| |
| switch (yyn) |
| { |
| ]b4_user_actions[ |
| default: break; |
| } |
| |
| ]b4_parse_trace_if([[ |
| yy_symbol_print ("-> $$ =", to!SymbolKind (yyr1_[yyn]), yyval]b4_locations_if([, yyloc])[);]])[ |
| |
| yystack.pop (yylen); |
| yylen = 0; |
| |
| /* Shift the result of the reduction. */ |
| int yystate = yyLRGotoState(yystack.stateAt(0), yyr1_[yyn]); |
| yystack.push (yystate, yyval]b4_locations_if([, yyloc])[); |
| return YYNEWSTATE; |
| } |
| |
| ]b4_parse_trace_if([[ |
| /*--------------------------------. |
| | Print this symbol on YYOUTPUT. | |
| `--------------------------------*/ |
| |
| private final void yy_symbol_print (string s, SymbolKind yykind, |
| ref Value yyval]b4_locations_if([, ref Location yyloc])[) |
| { |
| if (0 < yydebug) |
| { |
| File yyo = yyDebugStream; |
| yyo.write(s); |
| yyo.write(yykind < yyntokens_ ? " token " : " nterm "); |
| yyo.write(format("%s", yykind)); |
| yyo.write(" ("]b4_locations_if([ ~ yyloc.toString() ~ ": "])[); |
| ]b4_symbol_actions([printer])[ |
| yyo.write(")\n"); |
| } |
| } |
| ]])[ |
| ]b4_symbol_type_define[ |
| ]b4_push_if([[ |
| /** |
| * Push Parse input from external lexer |
| * |
| * @@param yyla current Symbol |
| * |
| * @@return <tt>YYACCEPT, YYABORT, YYPUSH_MORE</tt> |
| */ |
| public int pushParse(Symbol yyla)]], [[ |
| /** |
| * Parse input from the scanner that was specified at object construction |
| * time. Return whether the end of the input was reached successfully. |
| * |
| * @@return <tt>true</tt> if the parsing succeeds. Note that this does not |
| * imply that there were no syntax errors. |
| */ |
| public bool parse()]])[ |
| {]b4_push_if([[ |
| if (!this.pushParseInitialized) |
| { |
| pushParseInitialize(); |
| yyerrstatus_ = 0; |
| } |
| else |
| label = YYGETTOKEN; |
| |
| bool push_token_consumed = true; |
| ]], [[ bool yyresult;]b4_lac_if([[ |
| // Discard the LAC context in case there still is one left from a |
| // previous invocation. |
| yylacDiscard("init");]])[]b4_parse_trace_if([[ |
| |
| yycdebugln ("Starting parse");]])[ |
| yyerrstatus_ = 0; |
| |
| ]m4_ifdef([b4_initial_action], [ |
| m4_pushdef([b4_at_dollar], [yylloc])dnl |
| m4_pushdef([b4_dollar_dollar], [yylval])dnl |
| /* User initialization code. */ |
| b4_user_initial_action |
| m4_popdef([b4_dollar_dollar])dnl |
| m4_popdef([b4_at_dollar])])dnl |
| |
| [ /* Initialize the stack. */ |
| yystack.push (yystate, yylval]b4_locations_if([, yylloc])[); |
| |
| label = YYNEWSTATE;]])[ |
| for (;;) |
| final switch (label) |
| { |
| /* New state. Unlike in the C/C++ skeletons, the state is already |
| pushed when we come here. */ |
| case YYNEWSTATE:]b4_parse_trace_if([[ |
| yycdebugln (format("Entering state %d", yystate)); |
| if (0 < yydebug) |
| yystack.print (yyDebugStream);]])[ |
| |
| /* Accept? */ |
| if (yystate == yyfinal_)]b4_push_if([[ |
| { |
| label = YYACCEPT; |
| break; |
| }]], [[ |
| return true;]])[ |
| |
| /* Take a decision. First try without lookahead. */ |
| yyn = yypact_[yystate]; |
| if (yyPactValueIsDefault(yyn)) |
| { |
| label = YYDEFAULT; |
| break; |
| }]b4_push_if([[ |
| goto case; |
| |
| case YYGETTOKEN:]])[ |
| |
| /* Read a lookahead token. */ |
| if (yytoken == ]b4_symbol(empty, kind)[) |
| {]b4_push_if([[ |
| if (!push_token_consumed) |
| return YYPUSH_MORE;]])[]b4_parse_trace_if([[ |
| yycdebugln ("Reading a token");]])[]b4_push_if([[ |
| yytoken = yyla.token; |
| yylval = yyla.value;]b4_locations_if([[ |
| yylloc = yyla.location;]])[ |
| push_token_consumed = false;]], [[ |
| Symbol yysymbol = yylex(); |
| yytoken = yysymbol.token(); |
| yylval = yysymbol.value();]b4_locations_if([[ |
| yylloc = yysymbol.location();]])[]])[ |
| } |
| |
| /* Token already converted to internal form. */]b4_parse_trace_if([[ |
| yy_symbol_print ("Next token is", yytoken, yylval]b4_locations_if([, yylloc])[);]])[ |
| |
| if (yytoken == ]b4_symbol(error, kind)[) |
| { |
| // The scanner already issued an error message, process directly |
| // to error recovery. But do not keep the error token as |
| // lookahead, it is too special and may lead us to an endless |
| // loop in error recovery. */ |
| yytoken = ]b4_symbol(undef, kind)[;]b4_locations_if([[ |
| yyerrloc = yylloc;]])[ |
| label = YYERRLAB1; |
| } |
| else |
| { |
| /* If the proper action on seeing token YYTOKEN is to reduce or to |
| detect an error, take that action. */ |
| yyn += yytoken; |
| if (yyn < 0 || yylast_ < yyn || yycheck_[yyn] != yytoken) {]b4_lac_if([[ |
| if (!yylacEstablish(yystack, yytoken)) |
| label = YYERRLAB; |
| else]])[ |
| label = YYDEFAULT; |
| } |
| /* <= 0 means reduce or error. */ |
| else if ((yyn = yytable_[yyn]) <= 0) |
| { |
| if (yyTableValueIsError(yyn)) |
| label = YYERRLAB;]b4_lac_if([[ |
| else if (!yylacEstablish(yystack, yytoken)) |
| label = YYERRLAB;]])[ |
| else |
| { |
| yyn = -yyn; |
| label = YYREDUCE; |
| } |
| } |
| else |
| { |
| /* Shift the lookahead token. */]b4_parse_trace_if([[ |
| yy_symbol_print ("Shifting", yytoken, yylval]b4_locations_if([, yylloc])[);]])[ |
| |
| /* Discard the token being shifted. */ |
| yytoken = ]b4_symbol(empty, kind)[; |
| |
| /* Count tokens shifted since error; after three, turn off error |
| * status. */ |
| if (yyerrstatus_ > 0) |
| --yyerrstatus_; |
| |
| yystate = yyn; |
| yystack.push (yystate, yylval]b4_locations_if([, yylloc])[);]b4_lac_if([[ |
| yylacDiscard("shift");]])[ |
| label = YYNEWSTATE; |
| } |
| } |
| break; |
| |
| /*-----------------------------------------------------------. |
| | yydefault -- do the default action for the current state. | |
| `-----------------------------------------------------------*/ |
| case YYDEFAULT: |
| yyn = yydefact_[yystate]; |
| if (yyn == 0) |
| label = YYERRLAB; |
| else |
| label = YYREDUCE; |
| break; |
| |
| /*-----------------------------. |
| | yyreduce -- Do a reduction. | |
| `-----------------------------*/ |
| case YYREDUCE: |
| yylen = yyr2_[yyn]; |
| label = yyaction (yyn, yystack, yylen); |
| yystate = yystack.stateAt (0); |
| break; |
| |
| /*--------------------------------------. |
| | yyerrlab -- here on detecting error. | |
| `--------------------------------------*/ |
| case YYERRLAB: |
| /* If not already recovering from an error, report this error. */ |
| if (yyerrstatus_ == 0) |
| { |
| ++yynerrs_; |
| yyreportSyntaxError(new Context(]b4_lac_if([[this, ]])[yystack, yytoken]b4_locations_if([[, yylloc]])[)); |
| } |
| ]b4_locations_if([ |
| yyerrloc = yylloc;])[ |
| if (yyerrstatus_ == 3) |
| { |
| /* If just tried and failed to reuse lookahead token after an |
| * error, discard it. */ |
| |
| /* Return failure if at end of input. */ |
| if (yytoken == ]b4_symbol(eof, [kind])[)]b4_push_if([[ |
| { |
| label = YYABORT; |
| break; |
| }]], [[ |
| return false;]])[ |
| else |
| yytoken = ]b4_symbol(empty, kind)[; |
| } |
| |
| /* Else will try to reuse lookahead token after shifting the error |
| * token. */ |
| label = YYERRLAB1; |
| break; |
| |
| /*-------------------------------------------------. |
| | errorlab -- error raised explicitly by YYERROR. | |
| `-------------------------------------------------*/ |
| case YYERROR:]b4_locations_if([ |
| yyerrloc = yystack.locationAt (yylen - 1);])[ |
| /* Do not reclaim the symbols of the rule which action triggered |
| this YYERROR. */ |
| yystack.pop (yylen); |
| yylen = 0; |
| yystate = yystack.stateAt (0); |
| label = YYERRLAB1; |
| break; |
| |
| /*-------------------------------------------------------------. |
| | yyerrlab1 -- common code for both syntax error and YYERROR. | |
| `-------------------------------------------------------------*/ |
| case YYERRLAB1: |
| yyerrstatus_ = 3; /* Each real token shifted decrements this. */ |
| |
| // Pop stack until we find a state that shifts the error token. |
| for (;;) |
| { |
| yyn = yypact_[yystate]; |
| if (!yyPactValueIsDefault(yyn)) |
| { |
| yyn += ]b4_symbol(error, kind)[; |
| if (0 <= yyn && yyn <= yylast_ && yycheck_[yyn] == ]b4_symbol(error, kind)[) |
| { |
| yyn = yytable_[yyn]; |
| if (0 < yyn) |
| break; |
| } |
| } |
| |
| /* Pop the current state because it cannot handle the error token. */ |
| if (yystack.height == 1)]b4_push_if([[ |
| { |
| label = YYABORT; |
| break; |
| }]],[[ |
| return false;]])[ |
| |
| ]b4_locations_if([ yyerrloc = yystack.locationAt (0);])[ |
| yystack.pop (); |
| yystate = yystack.stateAt (0);]b4_parse_trace_if([[ |
| if (0 < yydebug) |
| yystack.print (yyDebugStream);]])[ |
| }]b4_push_if([[ |
| if (label == YYABORT) |
| /* Leave the switch. */ |
| break; |
| ]])[ |
| ]b4_locations_if([ |
| /* Muck with the stack to setup for yylloc. */ |
| yystack.push (0, yy_semantic_null, yylloc); |
| yystack.push (0, yy_semantic_null, yyerrloc); |
| yyloc = yylloc_from_stack (yystack, 2); |
| yystack.pop (2);])[ |
| |
| /* Shift the error token. */]b4_lac_if([[ |
| yylacDiscard("error recovery");]])[]b4_parse_trace_if([[ |
| yy_symbol_print ("Shifting", to!SymbolKind (yystos_[yyn]), yylval]b4_locations_if([, yyloc])[);]])[ |
| yystate = yyn; |
| yystack.push (yyn, yylval]b4_locations_if([, yyloc])[); |
| label = YYNEWSTATE; |
| break; |
| |
| /* Accept. */ |
| case YYACCEPT:]b4_push_if([[ |
| this.pushParseInitialized = false;]b4_parse_trace_if([[ |
| if (0 < yydebug) |
| yystack.print (yyDebugStream);]])[ |
| return YYACCEPT;]], [[ |
| yyresult = true; |
| label = YYRETURN; |
| break;]])[ |
| |
| /* Abort. */ |
| case YYABORT:]b4_push_if([[ |
| this.pushParseInitialized = false;]b4_parse_trace_if([[ |
| if (0 < yydebug) |
| yystack.print (yyDebugStream);]])[ |
| return YYABORT;]], [[ |
| yyresult = false; |
| label = YYRETURN; |
| break;]])[ |
| ]b4_push_if([[]], [[ ][case YYRETURN:]b4_parse_trace_if([[ |
| if (0 < yydebug) |
| yystack.print (yyDebugStream);]])[ |
| return yyresult;]])[ |
| } |
| assert(0); |
| } |
| |
| ]b4_push_if([[ |
| bool pushParseInitialized = false; |
| |
| /** |
| * (Re-)Initialize the state of the push parser. |
| */ |
| public void pushParseInitialize() |
| { |
| |
| /* Lookahead and lookahead in internal form. */ |
| this.yytoken = ]b4_symbol(empty, kind)[; |
| |
| /* State. */ |
| this.yyn = 0; |
| this.yylen = 0; |
| this.yystate = 0; |
| destroy(this.yystack); |
| this.label = YYNEWSTATE; |
| ]b4_lac_if([[ |
| destroy(this.yylacStack); |
| this.yylacEstablished = false;]])[ |
| |
| /* Error handling. */ |
| this.yynerrs_ = 0; |
| ]b4_locations_if([ |
| /* The location where the error started. */ |
| this.yyerrloc = Location(Position(), Position()); |
| this.yylloc = Location(Position(), Position());])[ |
| |
| /* Semantic value of the lookahead. */ |
| //destroy(this.yylval); |
| |
| /* Initialize the stack. */ |
| yystack.push(this.yystate, this.yylval]b4_locations_if([, this.yylloc])[); |
| |
| this.pushParseInitialized = true; |
| }]])[]b4_both_if([[ |
| /** |
| * Parse input from the scanner that was specified at object construction |
| * time. Return whether the end of the input was reached successfully. |
| * This version of parse() is defined only when api.push-push=both. |
| * |
| * @@return <tt>true</tt> if the parsing succeeds. Note that this does not |
| * imply that there were no syntax errors. |
| */ |
| bool parse() |
| { |
| int status = 0; |
| do { |
| status = this.pushParse(yylex()); |
| } while (status == YYPUSH_MORE); |
| return status == YYACCEPT; |
| }]])[ |
| |
| // Generate an error message. |
| private final void yyreportSyntaxError(Context yyctx) |
| {]b4_parse_error_bmatch( |
| [custom], [[ |
| yylexer.reportSyntaxError(yyctx);]], |
| [detailed], [[ |
| if (yyctx.getToken() != ]b4_symbol(empty, kind)[) |
| { |
| // FIXME: This method of building the message is not compatible |
| // with internationalization. |
| immutable int argmax = 5; |
| SymbolKind[] yyarg = new SymbolKind[argmax]; |
| int yycount = yysyntaxErrorArguments(yyctx, yyarg, argmax); |
| string res, yyformat; |
| switch (yycount) |
| { |
| case 1: |
| yyformat = YY_("syntax error, unexpected %s"); |
| res = format(yyformat, yyarg[0]); |
| break; |
| case 2: |
| yyformat = YY_("syntax error, unexpected %s, expecting %s"); |
| res = format(yyformat, yyarg[0], yyarg[1]); |
| break; |
| case 3: |
| yyformat = YY_("syntax error, unexpected %s, expecting %s or %s"); |
| res = format(yyformat, yyarg[0], yyarg[1], yyarg[2]); |
| break; |
| case 4: |
| yyformat = YY_("syntax error, unexpected %s, expecting %s or %s or %s"); |
| res = format(yyformat, yyarg[0], yyarg[1], yyarg[2], yyarg[3]); |
| break; |
| case 5: |
| yyformat = YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"); |
| res = format(yyformat, yyarg[0], yyarg[1], yyarg[2], yyarg[3], yyarg[4]); |
| break; |
| default: |
| res = YY_("syntax error"); |
| break; |
| } |
| yyerror(]b4_locations_if([yyctx.getLocation(), ])[res); |
| }]], |
| [[simple]], [[ |
| yyerror(]b4_locations_if([yyctx.getLocation(), ])[YY_("syntax error"));]])[ |
| } |
| |
| ]b4_parse_error_bmatch( |
| [detailed], [[ |
| private int yysyntaxErrorArguments(Context yyctx, SymbolKind[] yyarg, int yyargn) { |
| /* There are many possibilities here to consider: |
| - If this state is a consistent state with a default action, |
| then the only way this function was invoked is if the |
| default action is an error action. In that case, don't |
| check for expected tokens because there are none. |
| - The only way there can be no lookahead present (in tok) is |
| if this state is a consistent state with a default action. |
| Thus, detecting the absence of a lookahead is sufficient to |
| determine that there is no unexpected or expected token to |
| report. In that case, just report a simple "syntax error". |
| - Don't assume there isn't a lookahead just because this |
| state is a consistent state with a default action. There |
| might have been a previous inconsistent state, consistent |
| state with a non-default action, or user semantic action |
| that manipulated yychar. (However, yychar is currently out |
| of scope during semantic actions.) |
| - Of course, the expected token list depends on states to |
| have correct lookahead information, and it depends on the |
| parser not to perform extra reductions after fetching a |
| lookahead from the scanner and before detecting a syntax |
| error. Thus, state merging (from LALR or IELR) and default |
| reductions corrupt the expected token list. However, the |
| list is correct for canonical LR with one exception: it |
| will still contain any token that will not be accepted due |
| to an error action in a later state. |
| */ |
| int yycount = 0; |
| if (yyctx.getToken() != ]b4_symbol(empty, kind)[) |
| { |
| if (yyarg !is null) |
| yyarg[yycount] = yyctx.getToken(); |
| yycount += 1; |
| yycount += yyctx.getExpectedTokens(yyarg, 1, yyargn); |
| } |
| return yycount; |
| } |
| ]])[ |
| |
| |
| /** |
| * Information needed to get the list of expected tokens and to forge |
| * a syntax error diagnostic. |
| */ |
| public static final class Context |
| {]b4_lac_if([[ |
| private ]b4_parser_class[ yyparser;]])[ |
| private const(YYStack) yystack; |
| private SymbolKind yytoken;]b4_locations_if([[ |
| private const(Location) yylocation;]])[ |
| |
| this(]b4_lac_if([[]b4_parser_class[ parser, ]])[YYStack stack, SymbolKind kind]b4_locations_if([[, Location loc]])[) |
| {]b4_lac_if([[ |
| yyparser = parser;]])[ |
| yystack = stack; |
| yytoken = kind;]b4_locations_if([[ |
| yylocation = loc;]])[ |
| } |
| |
| final SymbolKind getToken() const |
| { |
| return yytoken; |
| }]b4_locations_if([[ |
| |
| final const(Location) getLocation() const |
| { |
| return yylocation; |
| }]])[ |
| /** |
| * Put in YYARG at most YYARGN of the expected tokens given the |
| * current YYCTX, and return the number of tokens stored in YYARG. If |
| * YYARG is null, return the number of expected tokens (guaranteed to |
| * be less than YYNTOKENS). |
| */ |
| int getExpectedTokens(SymbolKind[] yyarg, int yyargn)]b4_lac_if([[]], [[ const]])[ |
| { |
| return getExpectedTokens(yyarg, 0, yyargn); |
| } |
| |
| int getExpectedTokens(SymbolKind[] yyarg, int yyoffset, int yyargn)]b4_lac_if([[]], [[ const]])[ |
| { |
| int yycount = yyoffset;]b4_lac_if([b4_parse_trace_if([[ |
| // Execute LAC once. We don't care if it is successful, we |
| // only do it for the sake of debugging output. |
| |
| if (!yyparser.yylacEstablished) |
| yyparser.yylacCheck(yystack, yytoken); |
| ]])[ |
| for (int yyx = 0; yyx < yyntokens_; ++yyx) |
| { |
| SymbolKind yysym = SymbolKind(yyx); |
| if (yysym != ]b4_symbol(error, kind)[ |
| && yysym != ]b4_symbol(undef, kind)[ |
| && yyparser.yylacCheck(yystack, yysym)) |
| { |
| if (yyarg == null) |
| yycount += 1; |
| else if (yycount == yyargn) |
| return 0; |
| else |
| yyarg[yycount++] = yysym; |
| } |
| }]], [[ |
| int yyn = yypact_[this.yystack.stateAt(0)]; |
| if (!yyPactValueIsDefault(yyn)) |
| { |
| /* Start YYX at -YYN if negative to avoid negative |
| indexes in YYCHECK. In other words, skip the first |
| -YYN actions for this state because they are default |
| actions. */ |
| int yyxbegin = yyn < 0 ? -yyn : 0; |
| /* Stay within bounds of both yycheck and yytname. */ |
| int yychecklim = yylast_ - yyn + 1; |
| int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_; |
| for (int yyx = yyxbegin; yyx < yyxend; ++yyx) |
| if (yycheck_[yyx + yyn] == yyx && yyx != ]b4_symbol(error, kind)[ |
| && !yyTableValueIsError(yytable_[yyx + yyn])) |
| { |
| if (yyarg is null) |
| ++yycount; |
| else if (yycount == yyargn) |
| return 0; |
| else |
| yyarg[yycount++] = SymbolKind(yyx); |
| } |
| }]])[ |
| if (yyarg !is null && yycount == yyoffset && yyoffset < yyargn) |
| yyarg[yyoffset] = ]b4_symbol(empty, kind)[; |
| return yycount - yyoffset; |
| } |
| } |
| |
| ]b4_lac_if([[ |
| /** Check the lookahead yytoken. |
| * \returns true iff the token will be eventually shifted. |
| */ |
| bool yylacCheck(const YYStack yystack, SymbolKind yytoken) |
| { |
| // Logically, the yylacStack's lifetime is confined to this function. |
| // Clear it, to get rid of potential left-overs from previous call. |
| destroy(yylacStack); |
| // Reduce until we encounter a shift and thereby accept the token. |
| ]b4_parse_trace_if([[ |
| yycdebug("LAC: checking lookahead " ~ format("%s", yytoken) ~ ":");]])[ |
| int lacTop = 0; |
| while (true) |
| { |
| int topState = (yylacStack.length == 0 |
| ? yystack.stateAt(lacTop) |
| : yylacStack[$ - 1]); |
| int yyrule = yypact_[topState]; |
| if (yyPactValueIsDefault(yyrule) |
| || (yyrule += yytoken) < 0 || yylast_ < yyrule |
| || yycheck_[yyrule] != yytoken) |
| { |
| // Use the default action. |
| yyrule = yydefact_[+topState]; |
| if (yyrule == 0) |
| {]b4_parse_trace_if([[ |
| yycdebugln(" Err");]])[ |
| return false; |
| } |
| } |
| else |
| { |
| // Use the action from yytable. |
| yyrule = yytable_[yyrule]; |
| if (yyTableValueIsError(yyrule)) |
| {]b4_parse_trace_if([[ |
| yycdebugln(" Err");]])[ |
| return false; |
| } |
| if (0 < yyrule) |
| {]b4_parse_trace_if([[ |
| yycdebugln(" S" ~ to!string(yyrule));]])[ |
| return true; |
| } |
| yyrule = -yyrule; |
| } |
| // By now we know we have to simulate a reduce. |
| ]b4_parse_trace_if([[ |
| yycdebug(" R" ~ to!string(yyrule - 1));]])[ |
| // Pop the corresponding number of values from the stack. |
| { |
| int yylen = yyr2_[yyrule]; |
| // First pop from the LAC stack as many tokens as possible. |
| int lacSize = cast (int) yylacStack.length; |
| if (yylen < lacSize) |
| { |
| yylacStack.length -= yylen; |
| yylen = 0; |
| } |
| else if (lacSize != 0) |
| { |
| destroy(yylacStack); |
| yylen -= lacSize; |
| } |
| // Only afterwards look at the main stack. |
| // We simulate popping elements by incrementing lacTop. |
| lacTop += yylen; |
| } |
| // Keep topState in sync with the updated stack. |
| topState = (yylacStack.length == 0 |
| ? yystack.stateAt(lacTop) |
| : yylacStack[$ - 1]); |
| // Push the resulting state of the reduction. |
| int state = yyLRGotoState(topState, yyr1_[yyrule]);]b4_parse_trace_if([[ |
| yycdebug(" G" ~ to!string(state));]])[ |
| yylacStack.length++; |
| yylacStack[$ - 1] = state; |
| } |
| } |
| |
| /** Establish the initial context if no initial context currently exists. |
| * \returns true iff the token will be eventually shifted. |
| */ |
| bool yylacEstablish(YYStack yystack, SymbolKind yytoken) |
| { |
| /* Establish the initial context for the current lookahead if no initial |
| context is currently established. |
| |
| We define a context as a snapshot of the parser stacks. We define |
| the initial context for a lookahead as the context in which the |
| parser initially examines that lookahead in order to select a |
| syntactic action. Thus, if the lookahead eventually proves |
| syntactically unacceptable (possibly in a later context reached via a |
| series of reductions), the initial context can be used to determine |
| the exact set of tokens that would be syntactically acceptable in the |
| lookahead's place. Moreover, it is the context after which any |
| further semantic actions would be erroneous because they would be |
| determined by a syntactically unacceptable token. |
| |
| yylacEstablish should be invoked when a reduction is about to be |
| performed in an inconsistent state (which, for the purposes of LAC, |
| includes consistent states that don't know they're consistent because |
| their default reductions have been disabled). |
| |
| For parse.lac=full, the implementation of yylacEstablish is as |
| follows. If no initial context is currently established for the |
| current lookahead, then check if that lookahead can eventually be |
| shifted if syntactic actions continue from the current context. */ |
| if (yylacEstablished) |
| return true; |
| else |
| {]b4_parse_trace_if([[ |
| yycdebugln("LAC: initial context established for " ~ format("%s", yytoken));]])[ |
| yylacEstablished = true; |
| return yylacCheck(yystack, yytoken); |
| } |
| } |
| |
| /** Discard any previous initial lookahead context because of event. |
| * \param event the event which caused the lookahead to be discarded. |
| * Only used for debbuging output. */ |
| void yylacDiscard(string event) |
| { |
| /* Discard any previous initial lookahead context because of Event, |
| which may be a lookahead change or an invalidation of the currently |
| established initial context for the current lookahead. |
| |
| The most common example of a lookahead change is a shift. An example |
| of both cases is syntax error recovery. That is, a syntax error |
| occurs when the lookahead is syntactically erroneous for the |
| currently established initial context, so error recovery manipulates |
| the parser stacks to try to find a new initial context in which the |
| current lookahead is syntactically acceptable. If it fails to find |
| such a context, it discards the lookahead. */ |
| if (yylacEstablished) |
| {]b4_parse_trace_if([[ |
| yycdebugln("LAC: initial context discarded due to " ~ event);]])[ |
| yylacEstablished = false; |
| } |
| } |
| |
| /** The stack for LAC. |
| * Logically, the yylacStack's lifetime is confined to the function |
| * yylacCheck. We just store it as a member of this class to hold |
| * on to the memory and to avoid frequent reallocations. |
| */ |
| int[] yylacStack; |
| /** Whether an initial LAC context was established. */ |
| bool yylacEstablished; |
| ]])[ |
| |
| /** |
| * Whether the given <code>yypact_</code> value indicates a defaulted state. |
| * @@param yyvalue the value to check |
| */ |
| private static bool yyPactValueIsDefault(int yyvalue) |
| { |
| return yyvalue == yypact_ninf_; |
| } |
| |
| /** |
| * Whether the given <code>yytable_</code> value indicates a syntax error. |
| * @@param yyvalue the value to check |
| */ |
| private static bool yyTableValueIsError(int yyvalue) |
| { |
| return yyvalue == yytable_ninf_; |
| } |
| |
| /* YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing |
| STATE-NUM. */ |
| private static immutable ]b4_int_type_for([b4_pact])[ yypact_ninf_ = ]b4_pact_ninf[; |
| |
| /* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. If |
| positive, shift that token. If negative, reduce the rule which |
| number is the opposite. If YYTABLE_NINF_, syntax error. */ |
| private static immutable ]b4_int_type_for([b4_table])[ yytable_ninf_ = ]b4_table_ninf[; |
| |
| ]b4_parser_tables_define[ |
| |
| ]b4_parse_trace_if([[ |
| /* YYRLINE[YYN] -- Source line where rule number YYN was defined. */ |
| private static immutable ]b4_int_type_for([b4_rline])[[] yyrline_ = |
| @{ |
| ]b4_rline[ |
| @}; |
| |
| // Report on the debug stream that the rule yyrule is going to be reduced. |
| private final void yy_reduce_print (int yyrule, ref YYStack yystack) |
| { |
| if (yydebug == 0) |
| return; |
| |
| int yylno = yyrline_[yyrule]; |
| int yynrhs = yyr2_[yyrule]; |
| /* Print the symbols being reduced, and their result. */ |
| yycdebugln (format("Reducing stack by rule %d (line %d):", |
| yyrule - 1, yylno)); |
| |
| /* The symbols being reduced. */ |
| for (int yyi = 0; yyi < yynrhs; yyi++) |
| yy_symbol_print (format(" $%d =", yyi + 1), |
| to!SymbolKind (yystos_[yystack.stateAt(yynrhs - (yyi + 1))]), |
| ]b4_rhs_value(yynrhs, yyi + 1)b4_locations_if([, |
| b4_rhs_location(yynrhs, yyi + 1)])[); |
| } |
| ]])[ |
| |
| private static auto yytranslate_ (int t) |
| { |
| ]b4_api_token_raw_if( |
| [[ return SymbolKind(t);]], |
| [[ /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */ |
| immutable ]b4_int_type_for([b4_translate])[[] translate_table = |
| @{ |
| ]b4_translate[ |
| @}; |
| |
| // Last valid token kind. |
| immutable int code_max = ]b4_code_max[; |
| |
| if (t <= 0) |
| return ]b4_symbol(eof, kind)[; |
| else if (t <= code_max) |
| return SymbolKind(translate_table[t]); |
| else |
| return ]b4_symbol(undef, kind)[;]])[ |
| } |
| |
| private static immutable int yylast_ = ]b4_last[; |
| private static immutable int yynnts_ = ]b4_nterms_number[; |
| private static immutable int yyfinal_ = ]b4_final_state_number[; |
| private static immutable int yyntokens_ = ]b4_tokens_number[; |
| |
| private final struct YYStackElement { |
| int state; |
| Value value;]b4_locations_if( |
| b4_location_type[[] location;])[ |
| } |
| |
| private final struct YYStack { |
| private YYStackElement[] stack = []; |
| |
| public final ulong height() |
| { |
| return stack.length; |
| } |
| |
| public final void push (int state, Value value]dnl |
| b4_locations_if([, ref Location loc])[) |
| { |
| stack ~= YYStackElement(state, value]b4_locations_if([, loc])[); |
| } |
| |
| public final void pop () |
| { |
| pop (1); |
| } |
| |
| public final void pop (int num) |
| { |
| stack.length -= num; |
| } |
| |
| public final int stateAt (int i) const |
| { |
| return stack[$-i-1].state; |
| } |
| |
| ]b4_locations_if([[ |
| public final ref Location locationAt (int i) |
| { |
| return stack[$-i-1].location; |
| }]])[ |
| |
| public final ref Value valueAt (int i) |
| { |
| return stack[$-i-1].value; |
| } |
| ]b4_parse_trace_if([[ |
| // Print the state stack on the debug stream. |
| public final void print (File stream) |
| { |
| stream.write ("Stack now"); |
| for (int i = 0; i < stack.length; i++) |
| stream.write (" ", stack[i].state); |
| stream.writeln (); |
| }]])[ |
| } |
| ]b4_percent_code_get[ |
| } |
| ]b4_percent_code_get([[epilogue]])[]dnl |
| b4_epilogue[]dnl |
| b4_output_end |