| /*============================================================================= |
| 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) |
| =============================================================================*/ |
| #if !defined(SPIRIT_EXPECT_FUNCTION_APR_29_2007_0558PM) |
| #define SPIRIT_EXPECT_FUNCTION_APR_29_2007_0558PM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/spirit/home/support/unused.hpp> |
| #include <boost/spirit/home/support/multi_pass_wrapper.hpp> |
| #include <boost/throw_exception.hpp> |
| |
| namespace boost { namespace spirit { namespace qi { namespace detail |
| { |
| template < |
| typename Iterator, typename Context |
| , typename Skipper, typename Exception> |
| struct expect_function |
| { |
| typedef Iterator iterator_type; |
| typedef Context context_type; |
| |
| expect_function( |
| Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper) |
| : first(first) |
| , last(last) |
| , context(context) |
| , skipper(skipper) |
| , is_first(true) |
| { |
| } |
| |
| template <typename Component, typename Attribute> |
| bool operator()(Component const& component, Attribute& attr) const |
| { |
| // if this is not the first component in the expect chain we |
| // need to flush any multi_pass iterator we might be acting on |
| if (!is_first) |
| spirit::traits::clear_queue(first); |
| |
| // if we are testing the first component in the sequence, |
| // return true if the parser fails, if this is not the first |
| // component, throw exception if the parser fails |
| if (!component.parse(first, last, context, skipper, attr)) |
| { |
| if (is_first) |
| { |
| is_first = false; |
| return true; // true means the match failed |
| } |
| boost::throw_exception(Exception(first, last, component.what(context))); |
| #if defined(BOOST_NO_EXCEPTIONS) |
| return true; // for systems not supporting exceptions |
| #endif |
| } |
| is_first = false; |
| return false; |
| } |
| |
| template <typename Component> |
| bool operator()(Component const& component) const |
| { |
| // if this is not the first component in the expect chain we |
| // need to flush any multi_pass iterator we might be acting on |
| if (!is_first) |
| spirit::traits::clear_queue(first); |
| |
| // if we are testing the first component in the sequence, |
| // return true if the parser fails, if this not the first |
| // component, throw exception if the parser fails |
| if (!component.parse(first, last, context, skipper, unused)) |
| { |
| if (is_first) |
| { |
| is_first = false; |
| return true; |
| } |
| boost::throw_exception(Exception(first, last, component.what(context))); |
| #if defined(BOOST_NO_EXCEPTIONS) |
| return false; // for systems not supporting exceptions |
| #endif |
| } |
| is_first = false; |
| return false; |
| } |
| |
| Iterator& first; |
| Iterator const& last; |
| Context& context; |
| Skipper const& skipper; |
| mutable bool is_first; |
| |
| private: |
| // silence MSVC warning C4512: assignment operator could not be generated |
| expect_function& operator= (expect_function const&); |
| }; |
| }}}} |
| |
| #endif |