ceph/src/boost/libs/spirit/example/qi/compiler_tutorial/calc7/main.cpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 =============================================================================*/
   7 ///////////////////////////////////////////////////////////////////////////////
   8 //
   9 //  Now we'll introduce variables and assignment. This time, we'll also
  10 //  be renaming some of the rules -- a strategy for a grander scheme
  11 //  to come ;-)
  12 //
  13 //  This version also shows off grammar modularization. Here you will
  14 //  see how expressions and statements are built as modular grammars.
  15 //
  16 //  [ JDG April 9, 2007 ]       spirit2
  17 //  [ JDG February 18, 2011 ]   Pure attributes. No semantic actions.
  18 //
  19 ///////////////////////////////////////////////////////////////////////////////
  20
  21 #include "statement.hpp"
  22 #include "vm.hpp"
  23 #include "compiler.hpp"
  24
  25 ///////////////////////////////////////////////////////////////////////////////
  26 //  Main program
  27 ///////////////////////////////////////////////////////////////////////////////
  28 int
  29 main()
  30 {
  31     std::cout << "/////////////////////////////////////////////////////////\n\n";
  32     std::cout << "Statement parser...\n\n";
  33     std::cout << "/////////////////////////////////////////////////////////\n\n";
  34     std::cout << "Type some statements... ";
  35     std::cout << "An empty line ends input, compiles, runs and prints results\n\n";
  36     std::cout << "Example:\n\n";
  37     std::cout << "    var a = 123;\n";
  38     std::cout << "    var b = 456;\n";
  39     std::cout << "    var c = a + b * 2;\n\n";
  40     std::cout << "-------------------------\n";
  41
  42     std::string str;
  43     std::string source;
  44     while (std::getline(std::cin, str))
  45     {
  46         if (str.empty())
  47             break;
  48         source += str + '\n';
  49     }
  50
  51     typedef std::string::const_iterator iterator_type;
  52     iterator_type iter = source.begin();
  53     iterator_type end = source.end();
  54
  55     client::vmachine vm;                                    // Our virtual machine
  56     client::code_gen::program program;                      // Our VM program
  57     client::ast::statement_list ast;                        // Our AST
  58
  59     client::error_handler<iterator_type>
  60         error_handler(iter, end);                           // Our error handler
  61     client::parser::statement<iterator_type>
  62         parser(error_handler);                              // Our parser
  63     client::code_gen::compiler
  64         compile(program, error_handler);                    // Our compiler
  65
  66     boost::spirit::ascii::space_type space;
  67     bool success = phrase_parse(iter, end, parser, space, ast);
  68
  69     std::cout << "-------------------------\n";
  70
  71     if (success && iter == end)
  72     {
  73         if (compile(ast))
  74         {
  75             std::cout << "Success\n";
  76             std::cout << "-------------------------\n";
  77             vm.execute(program());
  78
  79             std::cout << "-------------------------\n";
  80             std::cout << "Assembler----------------\n\n";
  81             program.print_assembler();
  82
  83             std::cout << "-------------------------\n";
  84             std::cout << "Results------------------\n\n";
  85             program.print_variables(vm.get_stack());
  86         }
  87         else
  88         {
  89             std::cout << "Compile failure\n";
  90         }
  91     }
  92     else
  93     {
  94         std::cout << "Parse failure\n";
  95     }
  96
  97     std::cout << "-------------------------\n\n";
  98     return 0;
  99 }
 100
 101