[Boost-commit] svn:boost r66939 - trunk/libs/spirit/example/qi

Subject: [Boost-commit] svn:boost r66939 - trunk/libs/spirit/example/qi
From: hartmut.kaiser_at_[hidden]
Date: 2010-11-30 19:21:59

Author: hkaiser
Date: 2010-11-30 19:21:58 EST (Tue, 30 Nov 2010)
New Revision: 66939
URL: http://svn.boost.org/trac/boost/changeset/66939

Log:
Spirit: adding one more calculator example, this time filling an utree
Added:
   trunk/libs/spirit/example/qi/calc_utree.cpp   (contents, props changed)
Text files modified: 
   trunk/libs/spirit/example/qi/Jamfile |     2 ++                                      
   1 files changed, 2 insertions(+), 0 deletions(-)

Modified: trunk/libs/spirit/example/qi/Jamfile
==============================================================================
--- trunk/libs/spirit/example/qi/Jamfile	(original)
+++ trunk/libs/spirit/example/qi/Jamfile	2010-11-30 19:21:58 EST (Tue, 30 Nov 2010)
@@ -62,6 +62,8 @@
     calc7/calc7c.cpp
     ;
 
+exe calc_utree : calc_utree.cpp ;
+
 exe mini_c_interp :
     mini_c/mini_c.cpp
     mini_c/mini_ca.cpp

Added: trunk/libs/spirit/example/qi/calc_utree.cpp
==============================================================================
--- (empty file)
+++ trunk/libs/spirit/example/qi/calc_utree.cpp	2010-11-30 19:21:58 EST (Tue, 30 Nov 2010)
@@ -0,0 +1,124 @@
+/*=============================================================================
+    Copyright (c) 2001-2010 Hartmut Kaiser
+    Copyright (c) 2001-2010 Joel de Guzman
+
+    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)
+=============================================================================*/
+///////////////////////////////////////////////////////////////////////////////
+//
+//  Plain calculator example demonstrating the grammar. The parser is a
+//  syntax checker only and does not do any semantic evaluation.
+//
+//  [ JDG May 10, 2002 ]        spirit1
+//  [ JDG March 4, 2007 ]       spirit2
+//  [ HK November 30, 2010 ]    spirit2/utree
+//
+///////////////////////////////////////////////////////////////////////////////
+
+// #define BOOST_SPIRIT_DEBUG
+
+#include <boost/config/warning_disable.hpp>
+#include <boost/spirit/include/qi.hpp>
+#include <boost/spirit/include/support_utree.hpp>
+
+#include <iostream>
+#include <string>
+
+namespace client
+{
+    namespace qi = boost::spirit::qi;
+    namespace ascii = boost::spirit::ascii;
+    namespace spirit = boost::spirit;
+
+    ///////////////////////////////////////////////////////////////////////////////
+    //  Our calculator grammar
+    ///////////////////////////////////////////////////////////////////////////////
+    template <typename Iterator>
+    struct calculator : qi::grammar<Iterator, ascii::space_type, spirit::utree()>
+    {
+        calculator() : calculator::base_type(expression)
+        {
+            using qi::uint_;
+            using qi::char_;
+
+            expression =
+                term
+                >> *(   (char_('+') >> term)
+                    |   (char_('-') >> term)
+                    )
+                ;
+
+            term =
+                factor
+                >> *(   (char_('*') >> factor)
+                    |   (char_('/') >> factor)
+                    )
+                ;
+
+            factor =
+                uint_
+                |   char_('(') >> expression >> char_(')')
+                |   (char_('-') >> factor)
+                |   (char_('+') >> factor)
+                ;
+
+            BOOST_SPIRIT_DEBUG_NODE(expression);
+            BOOST_SPIRIT_DEBUG_NODE(term);
+            BOOST_SPIRIT_DEBUG_NODE(factor);
+        }
+
+        qi::rule<Iterator, ascii::space_type, spirit::utree()> expression, term, factor;
+    };
+}
+
+///////////////////////////////////////////////////////////////////////////////
+//  Main program
+///////////////////////////////////////////////////////////////////////////////
+int
+main()
+{
+    std::cout << "/////////////////////////////////////////////////////////\n\n";
+    std::cout << "Expression parser...\n\n";
+    std::cout << "/////////////////////////////////////////////////////////\n\n";
+    std::cout << "Type an expression...or [q or Q] to quit\n\n";
+
+    using boost::spirit::ascii::space;
+    using boost::spirit::utree;
+    typedef std::string::const_iterator iterator_type;
+    typedef client::calculator<iterator_type> calculator;
+
+    calculator calc; // Our grammar
+
+    std::string str;
+    while (std::getline(std::cin, str))
+    {
+        if (str.empty() || str[0] == 'q' || str[0] == 'Q')
+            break;
+
+        std::string::const_iterator iter = str.begin();
+        std::string::const_iterator end = str.end();
+        utree ut;
+        bool r = phrase_parse(iter, end, calc, space, ut);
+
+        if (r && iter == end)
+        {
+            std::cout << "-------------------------\n";
+            std::cout << "Parsing succeeded: " << ut << "\n";
+            std::cout << "-------------------------\n";
+        }
+        else
+        {
+            std::string rest(iter, end);
+            std::cout << "-------------------------\n";
+            std::cout << "Parsing failed\n";
+            std::cout << "stopped at: \": " << rest << "\"\n";
+            std::cout << "-------------------------\n";
+        }
+    }
+
+    std::cout << "Bye... :-) \n\n";
+    return 0;
+}
+
+