# C++ skeleton for Bison
-# Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
-# 2010 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
[# 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()
b4_defines_if(
[@output(b4_spec_defines_file@)@
b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++],
- [2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010])
-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]])[
]b4_percent_define_ifdef([[location_type]], [],
[[#include "location.hh"]])[
+]b4_null_define[
+
/* Enabling traces. */
#ifndef YYDEBUG
# define YYDEBUG ]b4_debug_flag[
/* Redirection for backward compatibility. */
# define YYSTYPE 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@)@
b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++],
- [2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010])
+ [2002-2012])
b4_percent_code_get([[top]])[]dnl
m4_if(b4_prefix, [yy], [],
[
{
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
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_;
+ if (yychar == yyempty_)
+ yytoken = yyempty_;
error (yylloc, yysyntax_error_ (yystate, yytoken));
}
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. */
[int, int])[)
{]b4_error_verbose_if([[
std::string yyres;
- int yyn = yypact_[yystate];
- if (yypact_ninf_ < yyn && yyn <= yylast_)
+ // 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_)
{
+ 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_;
-
- // 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];
- yyarg[yycount++] = yytname_[yytoken];
for (int yyx = yyxbegin; yyx < yyxend; ++yyx)
if (yycheck_[yyx + yyn] == yyx && yyx != yyterror_
&& !yy_table_value_is_error_ (yytable_[yyx + yyn]))
else
yyarg[yycount++] = yytname_[yyx];
}
+ }
+ }
- char const* yyformat = 0;
+ 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_(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)
}
else
yyres += *yyp;
- }
- else
- yyres = YY_("syntax error");
return yyres;]], [[
return YY_("syntax error");]])[
}
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, 2007, 2008, 2009, 2010])[
-
-#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[]dnl
-]
m4_divert_pop(0)
projects / bison.git / blobdiff