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/*
Copyright (C) 2008-2015, 2018-2019 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/>.
*/
%require "3.2"
%debug
%language "c++"
%define api.token.constructor
%define api.value.type variant
%define api.location.file none
%define parse.assert
%locations
%code requires // *.hh
{
#include <string>
#include <vector>
typedef std::vector<std::string> strings_type;
}
%code // *.cc
{
#include <iostream>
#include <sstream>
namespace yy
{
// Prototype of the yylex function providing subsequent tokens.
static parser::symbol_type yylex ();
// Print a vector of strings.
std::ostream&
operator<< (std::ostream& o, const strings_type& ss)
{
o << '{';
const char *sep = "";
for (strings_type::const_iterator i = ss.begin (), end = ss.end ();
i != end; ++i)
{
o << sep << *i;
sep = ", ";
}
return o << '}';
}
}
// Convert to string.
template <typename T>
std::string
to_string (const T& t)
{
std::ostringstream o;
o << t;
return o.str ();
}
}
%token <::std::string> TEXT;
%token <int> NUMBER;
%printer { yyo << '(' << &$$ << ") " << $$; } <*>;
%token END_OF_FILE 0;
%type <::std::string> item;
%type <::std::vector<std::string>> list;
%%
result:
list { std::cout << $1 << '\n'; }
;
list:
%empty { /* Generates an empty string list */ }
| list item { std::swap ($$, $1); $$.push_back ($2); }
;
item:
TEXT
| NUMBER { $$ = to_string ($1); }
;
%%
namespace yy
{
// Use nullptr with pre-C++11.
#if !defined __cplusplus || __cplusplus < 201103L
# define NULLPTR 0
#else
# define NULLPTR nullptr
#endif
// The yylex function providing subsequent tokens:
// TEXT "I have three numbers for you."
// NUMBER 1
// NUMBER 2
// NUMBER 3
// TEXT "And that's all!"
// END_OF_FILE
static
parser::symbol_type
yylex ()
{
static int count = 0;
const int stage = count;
++count;
parser::location_type loc (NULLPTR, unsigned (stage + 1), unsigned (stage + 1));
switch (stage)
{
case 0:
return parser::make_TEXT ("I have three numbers for you.", loc);
case 1:
case 2:
case 3:
return parser::make_NUMBER (stage, loc);
case 4:
return parser::make_TEXT ("And that's all!", loc);
default:
return parser::make_END_OF_FILE (loc);
}
}
// Mandatory error function
void
parser::error (const parser::location_type& loc, const std::string& msg)
{
std::cerr << loc << ": " << msg << '\n';
}
}
int
main ()
{
yy::parser p;
p.set_debug_level (!!getenv ("YYDEBUG"));
return p.parse ();
}
// Local Variables:
// mode: C++
// End:
|
