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// Copyright (C) 2020 T. Zachary Laine
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//[ self_filling_symbol_table_example
#include <boost/parser/parser.hpp>
#include <iostream>
#include <string>
namespace bp = boost::parser;
int main()
{
//[ self_filling_symbol_table_table
bp::symbols<int> const symbols = {{"c", 8}};
assert(parse("c", symbols));
//]
//[ self_filling_symbol_table_action
auto const add_symbol = [&symbols](auto & ctx) {
using namespace bp::literals;
// symbols::insert() requires a string, not a single character.
char chars[2] = {_attr(ctx)[0_c], 0};
symbols.insert(ctx, chars, _attr(ctx)[1_c]);
};
//]
//[ self_filling_symbol_table_parser
auto const parser = (bp::char_ >> bp::int_)[add_symbol] >> symbols;
//]
//[ self_filling_symbol_table_parse
auto const result = parse("X 9 X", parser, bp::ws);
assert(result && *result == 9);
//]
(void)result;
//[ self_filling_symbol_table_after_parse
assert(!parse("X", symbols));
//]
}
//]
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