ceph/src/boost/libs/spirit/classic/example/fundamental/distinct/distinct_parser.cpp

   1 /*=============================================================================
   2     Copyright (c) 2003 Vaclav Vesely
   3     http://spirit.sourceforge.net/
   4
   5     Use, modification and distribution is subject to the Boost Software
   6     License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   7     http://www.boost.org/LICENSE_1_0.txt)
   8 =============================================================================*/
   9 #include <boost/assert.hpp>
  10 #include <iostream>
  11 #include <boost/cstdlib.hpp>
  12 #include <boost/spirit/include/classic_core.hpp>
  13 #include <boost/spirit/include/classic_distinct.hpp>
  14
  15 using namespace std;
  16 using namespace boost;
  17 using namespace BOOST_SPIRIT_CLASSIC_NS;
  18
  19 // keyword_p for C++
  20 // (for basic usage instead of std_p)
  21 const distinct_parser<> keyword_p("0-9a-zA-Z_");
  22
  23 // keyword_d for C++
  24 // (for mor intricate usage, for example together with symbol tables)
  25 const distinct_directive<> keyword_d("0-9a-zA-Z_");
  26
  27 struct my_grammar: public grammar<my_grammar>
  28 {
  29     template <typename ScannerT>
  30     struct definition
  31     {
  32         typedef rule<ScannerT> rule_t;
  33
  34         definition(my_grammar const& self)
  35         {
  36             top
  37                 =
  38                     keyword_p("declare") // use keyword_p instead of std_p
  39                 >>  !ch_p(':')
  40                 >>  keyword_d[str_p("ident")] // use keyword_d
  41                 ;
  42         }
  43
  44         rule_t top;
  45
  46         rule_t const& start() const
  47         {
  48             return top;
  49         }
  50     };
  51 };
  52
  53 int main()
  54 {
  55     my_grammar gram;
  56     parse_info<> info;
  57
  58     info = parse("declare ident", gram, space_p);
  59     BOOST_ASSERT(info.full); // valid input
  60
  61     info = parse("declare: ident", gram, space_p);
  62     BOOST_ASSERT(info.full); // valid input
  63
  64     info = parse("declareident", gram, space_p);
  65     BOOST_ASSERT(!info.hit); // invalid input
  66
  67     return exit_success;
  68 }