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/*=============================================================================
Copyright (c) 2011 Thomas Heller
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)
==============================================================================*/
#include <boost/phoenix/core.hpp>
#include <boost/phoenix/statement.hpp>
#include <boost/phoenix/operator.hpp>
#include <boost/phoenix/scope.hpp>
#include <iostream>
#include <boost/phoenix/scope/this.hpp>
template <typename T0>
void f(T0 t)
{
std::cout << t(1) << "\n";
std::cout << t(2) << "\n";
std::cout << t(3) << "\n";
std::cout << t(4) << "\n";
std::cout << t(5) << "\n";
std::cout << t(6) << "\n";
std::cout << t(7) << "\n";
}
template <typename T0>
void f_2(T0 t)
{
for(int i = 0; i < 10; ++i)
{
for(int j = 0; j < i; ++j)
{
std::cout << t(i, j) << " ";
}
std::cout << "\n";
}
}
int main()
{
//using boost::phoenix::_this;
using boost::phoenix::if_;
using boost::phoenix::if_else;
using boost::phoenix::val;
using boost::phoenix::let;
using boost::phoenix::nothing;
using boost::phoenix::arg_names::_1;
using boost::phoenix::arg_names::_2;
using boost::phoenix::local_names::_a;
f((
if_(_1 == 0)
[
std::cout << val("\n")
]
.else_
[
std::cout << _1 << " "
, this_(_1 - 1)
]
, val(0)
));
/*
f((
if_else(
_1 == 0
, _1
,this_(_1 - 1)
)
));
*/
f((
if_else(
_1 != 0
,this_(_1 - 1)
, _1
)
));
/*
f(( // fac(n) = n * fac(n-1); fac(1) = 1
if_else(
_1 <= 1
, 1
, _1 * _this(_1 - 1)
)
));
f(( // fac(n) = n * fac(n-1); fac(1) = 1
if_else(
_1 > 1
, let(_a = _this(_1-1))[_1 * _a]
, 1
)
));
f(( // fib(n) = fib(n-1) + fib(n-2); fib(0) = 0; fib(1) = 1
if_else(
_1 == 0
, 0
, if_else(
_1 == 1
, 1
, _this(_1 - 1) + _this(_1 - 2)
)
)
));
f_2(( // bin(n, k) = bin(n-1, k-1) + bin(n-1, k); bin(n, 0) = 1; bin(0, k) = 0
if_else(
_1 == 0
, 0
, if_else(
_2 == 0
, 1
, _this(_1 - 1, _2 - 1) + _this(_1 - 1, _2)
)
)
));
*/
}