Subject: [Boost-commit] svn:boost r57826 - trunk/libs/spirit/example/qi
From: hartmut.kaiser_at_[hidden]
Date: 2009-11-20 19:35:03
Author: hkaiser
Date: 2009-11-20 19:35:03 EST (Fri, 20 Nov 2009)
New Revision: 57826
URL: http://svn.boost.org/trac/boost/changeset/57826
Log:
Spirit: added a new Qi example
Added:
trunk/libs/spirit/example/qi/iter_pos.hpp (contents, props changed)
trunk/libs/spirit/example/qi/iter_pos_parser.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 2009-11-20 19:35:03 EST (Fri, 20 Nov 2009)
@@ -30,6 +30,8 @@
exe key_value_sequence_ordered : key_value_sequence_ordered.cpp ;
exe key_value_sequence_empty_value : key_value_sequence_empty_value.cpp ;
+exe iter_pos_parser : iter_pos_parser.cpp ;
+
exe calculator1 : calc1.cpp ;
exe calculator2 : calc2.cpp ;
exe calculator2_ast : calc2_ast.cpp ;
Added: trunk/libs/spirit/example/qi/iter_pos.hpp
==============================================================================
--- (empty file)
+++ trunk/libs/spirit/example/qi/iter_pos.hpp 2009-11-20 19:35:03 EST (Fri, 20 Nov 2009)
@@ -0,0 +1,83 @@
+// Copyright (c) 2001-2009 Hartmut Kaiser
+//
+// 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)
+
+#if !defined(ITER_POS_NOV_20_2009_1245PM)
+#define ITER_POS_NOV_20_2009_1245PM
+
+#include <boost/spirit/include/qi_parse.hpp>
+
+///////////////////////////////////////////////////////////////////////////////
+// definition the place holder
+namespace custom_parser
+{
+ BOOST_SPIRIT_TERMINAL(iter_pos);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// implementation the enabler
+namespace boost { namespace spirit
+{
+ // We want custom_parser::iter_pos to be usable as a terminal only,
+ // and only for parser expressions (qi::domain).
+ template <>
+ struct use_terminal<qi::domain, custom_parser::tag::iter_pos>
+ : mpl::true_
+ {};
+}}
+
+///////////////////////////////////////////////////////////////////////////////
+// implementation of the parser
+namespace custom_parser
+{
+ struct iter_pos_parser
+ : boost::spirit::qi::primitive_parser<iter_pos_parser>
+ {
+ // Define the attribute type exposed by this parser component
+ template <typename Context, typename Iterator>
+ struct attribute
+ {
+ typedef Iterator type;
+ };
+
+ // This function is called during the actual parsing process
+ template <typename Iterator, typename Context
+ , typename Skipper, typename Attribute>
+ bool parse(Iterator& first, Iterator const& last
+ , Context&, Skipper const& skipper, Attribute& attr) const
+ {
+ boost::spirit::qi::skip_over(first, last, skipper);
+ boost::spirit::traits::assign_to(first, attr);
+ return true;
+ }
+
+ // This function is called during error handling to create
+ // a human readable string for the error context.
+ template <typename Context>
+ boost::spirit::info what(Context&) const
+ {
+ return boost::spirit::info("iter_pos");
+ }
+ };
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// instantiation of the parser
+namespace boost { namespace spirit { namespace qi
+{
+ // This is the factory function object invoked in order to create
+ // an instance of our iter_pos_parser.
+ template <typename Modifiers>
+ struct make_primitive<custom_parser::tag::iter_pos, Modifiers>
+ {
+ typedef custom_parser::iter_pos_parser result_type;
+
+ result_type operator()(unused_type, unused_type) const
+ {
+ return result_type();
+ }
+ };
+}}}
+
+#endif
Added: trunk/libs/spirit/example/qi/iter_pos_parser.cpp
==============================================================================
--- (empty file)
+++ trunk/libs/spirit/example/qi/iter_pos_parser.cpp 2009-11-20 19:35:03 EST (Fri, 20 Nov 2009)
@@ -0,0 +1,51 @@
+// Copyright (c) 2001-2009 Hartmut Kaiser
+//
+// 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)
+
+// The purpose of this example is to show how a simple custom primitive parser
+// component can be written. We develop a custom parser exposing the current
+// iterator position as its attribute.
+//
+// For more information see: http://spirit.sourceforge.net/home/
+
+#include <boost/spirit/include/qi_parse_attr.hpp>
+#include <boost/spirit/include/qi_char.hpp>
+#include <boost/spirit/include/qi_operator.hpp>
+
+#include <string>
+#include "iter_pos.hpp"
+
+namespace qi = boost::spirit::qi;
+
+int main()
+{
+ using custom_parser::iter_pos;
+
+ std::string prefix, suffix; // attributes receiving the
+ std::string::iterator position; // parsed values
+
+ std::string input("prefix1234567");
+ std::string::iterator first = input.begin();
+ bool result =
+ qi::parse(first, input.end()
+ , +qi::alpha >> iter_pos >> +qi::digit
+ , prefix, position, suffix);
+
+ if (result)
+ {
+ std::cout << "-------------------------------- \n";
+ std::cout << "Parsing succeeded\n";
+ std::cout << "prefix is: " << prefix << "\n";
+ std::cout << "suffix is: " << suffix << "\n";
+ std::cout << "position is: " << std::distance(input.begin(), position) << "\n";
+ std::cout << "-------------------------------- \n";
+ }
+ else
+ {
+ std::cout << "-------------------------------- \n";
+ std::cout << "Parsing failed\n";
+ std::cout << "-------------------------------- \n";
+ }
+ return 0;
+}