# C++ skeleton for Bison
-# Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation,
-# Inc.
+# Copyright (C) 2002-2012 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
b4_defines_if([],
[b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
-# Backward compatibility.
-m4_define([b4_location_constructors])
-m4_include(b4_pkgdatadir/[location.cc])
+b4_percent_define_ifdef([[location_type]], [],
+ [# Backward compatibility.
+ m4_define([b4_location_constructors])
+ m4_include(b4_pkgdatadir/[location.cc])])
+m4_include(b4_pkgdatadir/[stack.hh])
# We do want M4 expansion after # for CPP macros.
m4_changecom()
m4_divert_push(0)dnl
b4_defines_if(
-[@output(b4_spec_defines_file@)
+[@output(b4_spec_defines_file@)@
b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++],
- [2002, 2003, 2004, 2005, 2006])
-dnl FIXME: This is wrong, we want computed header guards.
+ [2002-2012])
[
+/**
+ ** \file ]b4_spec_defines_file[
+ ** Define the ]b4_namespace_ref[::parser class.
+ */
+
/* C++ LALR(1) parser skeleton written by Akim Demaille. */
-#ifndef PARSER_HEADER_H
-# define PARSER_HEADER_H
+]b4_cpp_guard_open([b4_spec_defines_file])[
]b4_percent_code_get([[requires]])[
#include <string>
#include <iostream>
#include "stack.hh"
+]b4_percent_define_ifdef([[location_type]], [],
+ [[#include "location.hh"]])[
-]b4_namespace_open[
- class position;
- class location;
-]b4_namespace_close[
-
-#include "location.hh"
-
-/* Enabling traces. */
-#ifndef YYDEBUG
-# define YYDEBUG ]b4_debug_flag[
-#endif
-
-/* Enabling verbose error messages. */
-#ifdef YYERROR_VERBOSE
-# undef YYERROR_VERBOSE
-# define YYERROR_VERBOSE 1
-#else
-# define YYERROR_VERBOSE ]b4_error_verbose_flag[
-#endif
-
-/* Enabling the token table. */
-#ifndef YYTOKEN_TABLE
-# define YYTOKEN_TABLE ]b4_token_table[
-#endif
-
-/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
- If N is 0, then set CURRENT to the empty location which ends
- the previous symbol: RHS[0] (always defined). */
-
-#ifndef YYLLOC_DEFAULT
-# define YYLLOC_DEFAULT(Current, Rhs, N) \
-do { \
- if (N) \
- { \
- (Current).begin = (Rhs)[1].begin; \
- (Current).end = (Rhs)[N].end; \
- } \
- else \
- { \
- (Current).begin = (Current).end = (Rhs)[0].end; \
- } \
-} while (false)
-#endif
+]b4_YYDEBUG_define[
]b4_namespace_open[
{
public:
/// Symbol semantic values.
-#ifndef YYSTYPE
+#ifndef ]b4_api_PREFIX[STYPE
]m4_ifdef([b4_stype],
[ union semantic_type
{
};],
[m4_if(b4_tag_seen_flag, 0,
[[ typedef int semantic_type;]],
-[[ typedef YYSTYPE semantic_type;]])])[
+[[ typedef ]b4_api_PREFIX[STYPE semantic_type;]])])[
#else
- typedef YYSTYPE semantic_type;
+ typedef ]b4_api_PREFIX[STYPE semantic_type;
#endif
/// Symbol locations.
- typedef ]b4_percent_define_get([[location_type]])[ location_type;
+ typedef ]b4_percent_define_get([[location_type]],
+ [[location]])[ location_type;
/// Tokens.
struct token
{
/// \returns 0 iff parsing succeeded.
virtual int parse ();
+#if ]b4_api_PREFIX[DEBUG
/// The current debugging stream.
std::ostream& debug_stream () const;
/// Set the current debugging stream.
debug_level_type debug_level () const;
/// Set the current debugging level.
void set_debug_level (debug_level_type l);
+#endif
private:
/// Report a syntax error.
/// Generate an error message.
/// \param state the state where the error occurred.
/// \param tok the lookahead token.
- virtual std::string yysyntax_error_ (int yystate]dnl
-b4_error_verbose_if([, int tok])[);
+ virtual std::string yysyntax_error_ (int yystate, int tok);
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
/// \brief Report a symbol value on the debug stream.
/// \param yytype The token type.
/// \param yyvaluep Its semantic value.
/// The location stack.
location_stack_type yylocation_stack_;
+ /// Whether the given \c yypact_ value indicates a defaulted state.
+ /// \param yyvalue the value to check
+ static bool yy_pact_value_is_default_ (int yyvalue);
+
+ /// Whether the given \c yytable_ value indicates a syntax error.
+ /// \param yyvalue the value to check
+ static bool yy_table_value_is_error_ (int yyvalue);
+
/// Internal symbol numbers.
typedef ]b4_int_type_for([b4_translate])[ token_number_type;
/* Tables. */
static const ]b4_int_type_for([b4_pact])[ yypact_[];
static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
- /// For a state, default rule to reduce.
+ /// For a state, default reduction number.
/// Unless\a yytable_ specifies something else to do.
/// Zero means the default is an error.
static const ]b4_int_type_for([b4_defact])[ yydefact_[];
/// For a rule, its LHS.
static const ]b4_int_type_for([b4_r1])[ yyr1_[];
/// For a rule, its RHS length.
- static const ]b4_int_type_for([b4_r2])[ yyr2_[];
-
-#if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
- /// For a symbol, its name in clear.
- static const char* const yytname_[];
-#endif
+ static const ]b4_int_type_for([b4_r2])[ yyr2_[]; ]b4_error_verbose_if([
-#if YYERROR_VERBOSE
/// Convert the symbol name \a n to a form suitable for a diagnostic.
- virtual std::string yytnamerr_ (const char *n);
-#endif
+ static std::string yytnamerr_ (const char *n);])[
-#if YYDEBUG
+]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
+ /// For a symbol, its name in clear.
+ static const char* const yytname_[];
+]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
/// A type to store symbol numbers and -1.
typedef ]b4_int_type_for([b4_rhs])[ rhs_number_type;
/// A `-1'-separated list of the rules' RHS.
]b4_percent_define_flag_if([[global_tokens_and_yystype]],
[b4_token_defines(b4_tokens)
-#ifndef YYSTYPE
+#ifndef ]b4_api_PREFIX[STYPE
/* Redirection for backward compatibility. */
-# define YYSTYPE b4_namespace_ref::b4_parser_class_name::semantic_type
+# define ]b4_api_PREFIX[STYPE b4_namespace_ref::b4_parser_class_name::semantic_type
#endif
-])
-b4_percent_code_get([[provides]])[]dnl
-
-[#endif /* ! defined PARSER_HEADER_H */]
+])[
+]b4_percent_code_get([[provides]])[
+]b4_cpp_guard_close([b4_spec_defines_file])
])dnl
-@output(b4_parser_file_name@)
+@output(b4_parser_file_name@)@
b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++],
- [2002, 2003, 2004, 2005, 2006])
+ [2002-2012])
b4_percent_code_get([[top]])[]dnl
m4_if(b4_prefix, [yy], [],
[
#define yylex b4_prefix[]lex])[
/* First part of user declarations. */
-]b4_user_pre_prologue
+]b4_user_pre_prologue[
-b4_defines_if([[
+]b4_defines_if([[
#include "@basename(]b4_spec_defines_file[@)"]])[
/* User implementation prologue. */
-]b4_user_post_prologue
-b4_percent_code_get[]dnl
+]b4_user_post_prologue[
+]b4_percent_code_get[
-[#ifndef YY_
-# if YYENABLE_NLS
+]b4_null_define[
+
+#ifndef YY_
+# if defined YYENABLE_NLS && YYENABLE_NLS
# if ENABLE_NLS
# include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
# define YY_(msgid) dgettext ("bison-runtime", msgid)
# endif
#endif
+#define YYRHSLOC(Rhs, K) ((Rhs)[K])
+]b4_yylloc_default_define[
+
/* Suppress unused-variable warnings by "using" E. */
#define YYUSE(e) ((void) (e))
/* Enable debugging if requested. */
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
/* A pseudo ostream that takes yydebug_ into account. */
# define YYCDEBUG if (yydebug_) (*yycdebug_)
yystack_print_ (); \
} while (false)
-#else /* !YYDEBUG */
+#else /* !]b4_api_PREFIX[DEBUG */
# define YYCDEBUG if (false) std::cerr
# define YY_SYMBOL_PRINT(Title, Type, Value, Location)
# define YY_REDUCE_PRINT(Rule)
# define YY_STACK_PRINT()
-#endif /* !YYDEBUG */
+#endif /* !]b4_api_PREFIX[DEBUG */
#define yyerrok (yyerrstatus_ = 0)
#define yyclearin (yychar = yyempty_)
#define YYERROR goto yyerrorlab
#define YYRECOVERING() (!!yyerrstatus_)
-]b4_namespace_open[
-#if YYERROR_VERBOSE
+]b4_namespace_open[]b4_error_verbose_if([[
/* Return YYSTR after stripping away unnecessary quotes and
backslashes, so that it's suitable for yyerror. The heuristic is
return yystr;
}
-
-#endif
+]])[
/// Build a parser object.
]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
:])[
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
]m4_ifset([b4_parse_param], [ ], [ :])[yydebug_ (false),
yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
#endif]b4_parse_param_cons[
{
}
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
/*--------------------------------.
| Print this symbol on YYOUTPUT. |
`--------------------------------*/
{
YYUSE (yylocationp);
YYUSE (yyvaluep);
+ std::ostream& yyo = debug_stream ();
+ std::ostream& yyoutput = yyo;
+ YYUSE (yyoutput);
switch (yytype)
{
]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
yylocation_stack_.pop (n);
}
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
std::ostream&
]b4_parser_class_name[::debug_stream () const
{
}
#endif
+ inline bool
+ ]b4_parser_class_name[::yy_pact_value_is_default_ (int yyvalue)
+ {
+ return yyvalue == yypact_ninf_;
+ }
+
+ inline bool
+ ]b4_parser_class_name[::yy_table_value_is_error_ (int yyvalue)
+ {
+ return yyvalue == yytable_ninf_;
+ }
+
int
]b4_parser_class_name[::parse ()
{
/// Location of the lookahead.
location_type yylloc;
/// The locations where the error started and ended.
- location_type yyerror_range[2];
+ location_type yyerror_range[3];
/// $$.
semantic_type yyval;
/* Try to take a decision without lookahead. */
yyn = yypact_[yystate];
- if (yyn == yypact_ninf_)
+ if (yy_pact_value_is_default_ (yyn))
goto yydefault;
/* Read a lookahead token. */
{
YYCDEBUG << "Reading a token: ";
yychar = ]b4_c_function_call([yylex], [int],
- [[YYSTYPE*], [&yylval]][]dnl
+ [b4_api_PREFIX[STYPE*], [&yylval]][]dnl
b4_locations_if([, [[location*], [&yylloc]]])dnl
m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
}
yyn = yytable_[yyn];
if (yyn <= 0)
{
- if (yyn == 0 || yyn == yytable_ninf_)
- goto yyerrlab;
+ if (yy_table_value_is_error_ (yyn))
+ goto yyerrlab;
yyn = -yyn;
goto yyreduce;
}
switch (yyn)
{
]b4_user_actions[
- default: break;
+ default:
+ break;
}
+ /* User semantic actions sometimes alter yychar, and that requires
+ that yytoken be updated with the new translation. We take the
+ approach of translating immediately before every use of yytoken.
+ One alternative is translating here after every semantic action,
+ but that translation would be missed if the semantic action
+ invokes YYABORT, YYACCEPT, or YYERROR immediately after altering
+ yychar. In the case of YYABORT or YYACCEPT, an incorrect
+ destructor might then be invoked immediately. In the case of
+ YYERROR, subsequent parser actions might lead to an incorrect
+ destructor call or verbose syntax error message before the
+ lookahead is translated. */
YY_SYMBOL_PRINT ("-> $$ =", yyr1_[yyn], &yyval, &yyloc);
yypop_ (yylen);
| yyerrlab -- here on detecting error |
`------------------------------------*/
yyerrlab:
+ /* Make sure we have latest lookahead translation. See comments at
+ user semantic actions for why this is necessary. */
+ yytoken = yytranslate_ (yychar);
+
/* If not already recovering from an error, report this error. */
if (!yyerrstatus_)
{
++yynerrs_;
- error (yylloc, yysyntax_error_ (yystate]dnl
-b4_error_verbose_if([, yytoken])[));
+ if (yychar == yyempty_)
+ yytoken = yyempty_;
+ error (yylloc, yysyntax_error_ (yystate, yytoken));
}
- yyerror_range[0] = yylloc;
+ yyerror_range[1] = yylloc;
if (yyerrstatus_ == 3)
{
/* If just tried and failed to reuse lookahead token after an
if (false)
goto yyerrorlab;
- yyerror_range[0] = yylocation_stack_[yylen - 1];
+ yyerror_range[1] = yylocation_stack_[yylen - 1];
/* Do not reclaim the symbols of the rule which action triggered
this YYERROR. */
yypop_ (yylen);
for (;;)
{
yyn = yypact_[yystate];
- if (yyn != yypact_ninf_)
+ if (!yy_pact_value_is_default_ (yyn))
{
yyn += yyterror_;
if (0 <= yyn && yyn <= yylast_ && yycheck_[yyn] == yyterror_)
if (yystate_stack_.height () == 1)
YYABORT;
- yyerror_range[0] = yylocation_stack_[0];
+ yyerror_range[1] = yylocation_stack_[0];
yydestruct_ ("Error: popping",
yystos_[yystate],
&yysemantic_stack_[0], &yylocation_stack_[0]);
YY_STACK_PRINT ();
}
- yyerror_range[1] = yylloc;
+ yyerror_range[2] = yylloc;
// Using YYLLOC is tempting, but would change the location of
// the lookahead. YYLOC is available though.
- YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);
+ YYLLOC_DEFAULT (yyloc, yyerror_range, 2);
yysemantic_stack_.push (yylval);
yylocation_stack_.push (yyloc);
/* Shift the error token. */
YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],
- &yysemantic_stack_[0], &yylocation_stack_[0]);
+ &yysemantic_stack_[0], &yylocation_stack_[0]);
yystate = yyn;
goto yynewstate;
yyreturn:
if (yychar != yyempty_)
- yydestruct_ ("Cleanup: discarding lookahead", yytoken, &yylval, &yylloc);
+ {
+ /* Make sure we have latest lookahead translation. See comments
+ at user semantic actions for why this is necessary. */
+ yytoken = yytranslate_ (yychar);
+ yydestruct_ ("Cleanup: discarding lookahead", yytoken, &yylval,
+ &yylloc);
+ }
/* Do not reclaim the symbols of the rule which action triggered
this YYABORT or YYACCEPT. */
// Generate an error message.
std::string
- ]b4_parser_class_name[::yysyntax_error_ (int yystate]dnl
-b4_error_verbose_if([, int tok])[)
- {
- std::string res;
- YYUSE (yystate);
-#if YYERROR_VERBOSE
- int yyn = yypact_[yystate];
- if (yypact_ninf_ < yyn && yyn <= yylast_)
+ ]b4_parser_class_name[::yysyntax_error_ (]dnl
+b4_error_verbose_if([int yystate, int yytoken],
+ [int, int])[)
+ {]b4_error_verbose_if([[
+ std::string yyres;
+ // Number of reported tokens (one for the "unexpected", one per
+ // "expected").
+ size_t yycount = 0;
+ // Its maximum.
+ enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
+ // Arguments of yyformat.
+ char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
+
+ /* 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 yytoken) 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.
+ - 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.
+ */
+ if (yytoken != yyempty_)
{
- /* Start YYX at -YYN if negative to avoid negative indexes in
- YYCHECK. */
- 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_;
- int count = 0;
- for (int x = yyxbegin; x < yyxend; ++x)
- if (yycheck_[x + yyn] == x && x != yyterror_)
- ++count;
-
- // FIXME: This method of building the message is not compatible
- // with internationalization. It should work like yacc.c does it.
- // That is, first build a string that looks like this:
- // "syntax error, unexpected %s or %s or %s"
- // Then, invoke YY_ on this string.
- // Finally, use the string as a format to output
- // yytname_[tok], etc.
- // Until this gets fixed, this message appears in English only.
- res = "syntax error, unexpected ";
- res += yytnamerr_ (yytname_[tok]);
- if (count < 5)
- {
- count = 0;
- for (int x = yyxbegin; x < yyxend; ++x)
- if (yycheck_[x + yyn] == x && x != yyterror_)
- {
- res += (!count++) ? ", expecting " : " or ";
- res += yytnamerr_ (yytname_[x]);
- }
- }
+ yyarg[yycount++] = yytname_[yytoken];
+ int yyn = yypact_[yystate];
+ if (!yy_pact_value_is_default_ (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 != yyterror_
+ && !yy_table_value_is_error_ (yytable_[yyx + yyn]))
+ {
+ if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
+ {
+ yycount = 1;
+ break;
+ }
+ else
+ yyarg[yycount++] = yytname_[yyx];
+ }
+ }
}
- else
-#endif
- res = YY_("syntax error");
- return res;
+
+ char const* yyformat = YY_NULL;
+ switch (yycount)
+ {
+#define YYCASE_(N, S) \
+ case N: \
+ yyformat = S; \
+ break
+ YYCASE_(0, YY_("syntax error"));
+ YYCASE_(1, YY_("syntax error, unexpected %s"));
+ YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
+ YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
+ YYCASE_(4, YY_("syntax error, unexpected %s, expecting %s or %s or %s"));
+ YYCASE_(5, YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"));
+#undef YYCASE_
+ }
+
+ // Argument number.
+ size_t yyi = 0;
+ for (char const* yyp = yyformat; *yyp; ++yyp)
+ if (yyp[0] == '%' && yyp[1] == 's' && yyi < yycount)
+ {
+ yyres += yytnamerr_ (yyarg[yyi++]);
+ ++yyp;
+ }
+ else
+ yyres += *yyp;
+ return yyres;]], [[
+ return YY_("syntax error");]])[
}
]b4_pact[
};
- /* YYDEFACT[S] -- default rule to reduce with in state S when YYTABLE
- doesn't specify something else to do. Zero means the default is an
- error. */
+ /* YYDEFACT[S] -- default reduction number in state S. Performed when
+ YYTABLE doesn't specify something else to do. Zero means the
+ default is an error. */
const ]b4_int_type_for([b4_defact])[
]b4_parser_class_name[::yydefact_[] =
{
/* 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 zero, do what YYDEFACT says. */
+ number is the opposite. If YYTABLE_NINF_, syntax error. */
const ]b4_int_type(b4_table_ninf, b4_table_ninf) b4_parser_class_name::yytable_ninf_ = b4_table_ninf[;
const ]b4_int_type_for([b4_table])[
]b4_parser_class_name[::yytable_[] =
]b4_stos[
};
-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
/* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
to YYLEX-NUM. */
const ]b4_int_type_for([b4_toknum])[
]b4_r2[
};
-#if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
+]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
/* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
First, the terminals, then, starting at \a yyntokens_, nonterminals. */
const char*
{
]b4_tname[
};
-#endif
-#if YYDEBUG
+]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
/* YYRHS -- A `-1'-separated list of the rules' RHS. */
const ]b4_parser_class_name[::rhs_number_type
]b4_parser_class_name[::yyrhs_[] =
&]b4_rhs_value(yynrhs, yyi + 1)[,
&]b4_rhs_location(yynrhs, yyi + 1)[);
}
-#endif // YYDEBUG
+#endif // ]b4_api_PREFIX[DEBUG
/* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */
]b4_parser_class_name[::token_number_type
const ]b4_parser_class_name[::token_number_type ]b4_parser_class_name[::yyundef_token_ = ]b4_undef_token_number[;
]b4_namespace_close[
-
]b4_epilogue
-dnl
-@output(b4_dir_prefix[]stack.hh@)
-b4_copyright([Stack handling for Bison parsers in C++],
- [2002, 2003, 2004, 2005, 2006])[
-
-#ifndef BISON_STACK_HH
-# define BISON_STACK_HH
-
-#include <deque>
-
-]b4_namespace_open[
- template <class T, class S = std::deque<T> >
- class stack
- {
- public:
-
- // Hide our reversed order.
- typedef typename S::reverse_iterator iterator;
- typedef typename S::const_reverse_iterator const_iterator;
-
- stack () : seq_ ()
- {
- }
-
- stack (unsigned int n) : seq_ (n)
- {
- }
-
- inline
- T&
- operator [] (unsigned int i)
- {
- return seq_[i];
- }
-
- inline
- const T&
- operator [] (unsigned int i) const
- {
- return seq_[i];
- }
-
- inline
- void
- push (const T& t)
- {
- seq_.push_front (t);
- }
-
- inline
- void
- pop (unsigned int n = 1)
- {
- for (; n; --n)
- seq_.pop_front ();
- }
-
- inline
- unsigned int
- height () const
- {
- return seq_.size ();
- }
-
- inline const_iterator begin () const { return seq_.rbegin (); }
- inline const_iterator end () const { return seq_.rend (); }
-
- private:
-
- S seq_;
- };
-
- /// Present a slice of the top of a stack.
- template <class T, class S = stack<T> >
- class slice
- {
- public:
-
- slice (const S& stack,
- unsigned int range) : stack_ (stack),
- range_ (range)
- {
- }
-
- inline
- const T&
- operator [] (unsigned int i) const
- {
- return stack_[range_ - i];
- }
-
- private:
-
- const S& stack_;
- unsigned int range_;
- };
-]b4_namespace_close[
-
-#endif // not BISON_STACK_HH]
m4_divert_pop(0)