/*============================================================================= Copyright (c) 2003 Vaclav Vesely http://spirit.sourceforge.net/ Use, modification and distribution is subject to 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) =============================================================================*/ // // This example demonstrates usage of the parser_context template with // an explicit argument to declare rules with match results different from // nil_t. For better understanding, you should read the chapter "In-depth: // The Parser Context" in the documentation. // // The default context of non-terminals is the parser_context. // The parser_context is a template with one argument AttrT, which is the type // of match attribute. // // In this example int_rule is declared as rule with int match attribute's // type, so in int_rule variable we can hold any parser, which returns int // value. For example int_p or bin_p. And the most important is that we can // use returned value in the semantic action binded to the int_rule. // //----------------------------------------------------------------------------- #include #include #include #include using namespace std; using namespace boost; using namespace phoenix; using namespace BOOST_SPIRIT_CLASSIC_NS; //----------------------------------------------------------------------------- int main() { rule > int_rule = int_p; parse( "123", // Using a returned value in the semantic action int_rule[cout << arg1 << endl] ); return exit_success; } //-----------------------------------------------------------------------------