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/*=============================================================================
For Boost Bind:
Copyright (c) 2001-2004 Peter Dimov and Multi Media Ltd.
Copyright (c) 2001 David Abrahams
Copyright (c) 2005 Peter Dimov
For Boost Phoenix:
Copyright (c) 2001-2010 Joel de Guzman
Copyright (c) 2010 Thomas Heller
For the example:
Copyright (c) 2011 Paul Heil
Copyright (c) 2015 John Fletcher
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)
==============================================================================*/
// bind_goose.cpp
// This example is based on code by Paul Heil to be found here:
// http://www.codeproject.com/Tips/248492/How-does-boost-phoenix-improve-boost-bind
//
// Show different ways of using boost bind and phoenix to handle deletion.
//
#include <iostream>
#include <boost/function.hpp>
#include <boost/bind.hpp>
#include <boost/phoenix/core.hpp>
#include <boost/phoenix/bind.hpp>
#include <boost/phoenix/operator/comparison.hpp>
#include <boost/phoenix/stl/algorithm/transformation.hpp>
#include <functional>
#include <string>
#include <vector>
////////////////////////////////////////////
// Set up the list here
////////////////////////////////////////////
std::vector< std::string > make_list() {
std::vector< std::string > list;
list.push_back( "duck" );
list.push_back( "duck" );
list.push_back( "goose" );
return list;
}
//////////////////////////////////////////////
// First example using standard library only
//////////////////////////////////////////////
bool IsGoose( const std::string& s )
{
return s == "goose";
}
void delete_value1(std::vector< std::string > &list )
{
list.erase( std::remove_if( list.begin(), list.end(), IsGoose ), list.end() );
}
void out_string(const std::string &s)
{
std::cout << s << std::endl;
}
void show_list1( const std::vector< std::string > &list )
{
std::for_each(list.begin(), list.end(), out_string);
}
//////////////////////////////////////////////
// Second example using boost bind
//////////////////////////////////////////////
bool isValue(const std::string &s1, const std::string &s2)
{
return s1==s2;
}
void delete_value2(std::vector< std::string > &list, const std::string & value)
{
list.erase(
std::remove_if(
list.begin(),
list.end(),
boost::bind(
isValue, // &isValue works as well.
_1, // Boost.Bind placeholder
boost::cref( value ) ) ),
list.end() );
}
///////////////////////////////////////////////////////
// Third example using boost phoenix for the comparison
///////////////////////////////////////////////////////
namespace phx = boost::phoenix;
using phx::placeholders::arg1;
using phx::placeholders::arg2;
void delete_value3(std::vector< std::string > &list, const std::string & value)
{
list.erase( std::remove_if(
list.begin(),
list.end(),
// This needs header boost/phoenix/operator/comparison.
// arg1 is a Boost.Phoenix placeholder.
arg1 == phx::cref( value ) ),
list.end() );
}
//////////////////////////////////////////////////////////////
// Third example using boost phoenix for the algorithm as well
//////////////////////////////////////////////////////////////
void delete_value4(std::vector< std::string > &list, const std::string & value)
{
// This need header boost/phoenix/stl/algorithm/transformation
list.erase( phx::remove_if( arg1, arg2 )
( list, arg1 == phx::cref( value ) ),
list.end() );
}
int main() {
std::cout << "--------------------------------" << std::endl;
std::cout << "Delete the goose examples." << std::endl;
std::cout << "--------------------------------" << std::endl;
std::string value = "goose";
std::vector< std::string > list1 = make_list();
delete_value1(list1);
show_list1(list1);
std::cout << "--------------------------------" << std::endl;
std::vector< std::string > list2 = make_list();
delete_value2(list2,value);
show_list1(list2);
std::cout << "--------------------------------" << std::endl;
std::vector< std::string > list3 = make_list();
delete_value3(list3,value);
show_list1(list3);
std::cout << "--------------------------------" << std::endl;
std::vector< std::string > list4 = make_list();
delete_value4(list4,value);
show_list1(list4);
std::cout << "--------------------------------" << std::endl;
return 0;
}
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