ceph/src/boost/libs/spirit/example/x3/calc/calc8/main.cpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2014 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 //  [ JDG May 17, 2014 ]        Ported from qi calc7 example.
  19 //
  20 ///////////////////////////////////////////////////////////////////////////////
  21
  22 #include "ast.hpp"
  23 #include "vm.hpp"
  24 #include "compiler.hpp"
  25 #include "statement.hpp"
  26 #include "error_handler.hpp"
  27 #include "config.hpp"
  28 #include <iostream>
  29
  30 ///////////////////////////////////////////////////////////////////////////////
  31 //  Main program
  32 ///////////////////////////////////////////////////////////////////////////////
  33 int
  34 main()
  35 {
  36     std::cout << "/////////////////////////////////////////////////////////\n\n";
  37     std::cout << "Statement parser...\n\n";
  38     std::cout << "/////////////////////////////////////////////////////////\n\n";
  39     std::cout << "Type some statements... ";
  40     std::cout << "An empty line ends input, compiles, runs and prints results\n\n";
  41     std::cout << "Example:\n\n";
  42     std::cout << "    var a = 123;\n";
  43     std::cout << "    var b = 456;\n";
  44     std::cout << "    var c = a + b * 2;\n\n";
  45     std::cout << "-------------------------\n";
  46
  47     std::string str;
  48     std::string source;
  49     while (std::getline(std::cin, str))
  50     {
  51         if (str.empty())
  52             break;
  53         source += str + '\n';
  54     }
  55
  56     using client::parser::iterator_type;
  57     iterator_type iter(source.begin());
  58     iterator_type end(source.end());
  59
  60
  61     client::vmachine vm;                                    // Our virtual machine
  62     client::code_gen::program program;                      // Our VM program
  63     client::ast::statement_list ast;                        // Our AST
  64
  65     using boost::spirit::x3::with;
  66     using client::parser::error_handler_type;
  67     using client::parser::error_handler_tag;
  68     error_handler_type error_handler(iter, end, std::cerr); // Our error handler
  69
  70     // Our compiler
  71     client::code_gen::compiler compile(program, error_handler);
  72
  73     // Our parser
  74     auto const parser =
  75         // we pass our error handler to the parser so we can access
  76         // it later on in our on_error and on_sucess handlers
  77         with<error_handler_tag>(std::ref(error_handler))
  78         [
  79             client::statement()
  80         ];
  81
  82     using boost::spirit::x3::ascii::space;
  83     bool success = phrase_parse(iter, end, parser, space, ast);
  84
  85     std::cout << "-------------------------\n";
  86
  87     if (success && iter == end)
  88     {
  89         if (compile(ast))
  90         {
  91             std::cout << "Success\n";
  92             std::cout << "-------------------------\n";
  93             vm.execute(program());
  94
  95             std::cout << "-------------------------\n";
  96             std::cout << "Assembler----------------\n\n";
  97             program.print_assembler();
  98
  99             std::cout << "-------------------------\n";
 100             std::cout << "Results------------------\n\n";
 101             program.print_variables(vm.get_stack());
 102         }
 103         else
 104         {
 105             std::cout << "Compile failure\n";
 106         }
 107     }
 108     else
 109     {
 110         std::cout << "Parse failure\n";
 111     }
 112
 113     std::cout << "-------------------------\n\n";
 114     return 0;
 115 }