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/*=============================================================================
Copyright (c) 2017 Paul Fultz II
static_if.cpp
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)
==============================================================================*/
/*=============================================================================
Copyright (c) 2016 Paul Fultz II
static_if.cpp
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 "example.h"
using namespace boost::hof;
// static_if example taken from Baptiste Wicht:
// http://baptiste-wicht.com/posts/2015/07/simulate-static_if-with-c11c14.html
template<typename T>
void decrement_kindof(T& value)
{
eval(first_of(
if_(std::is_same<std::string, T>())([&](auto id){
id(value).pop_back();
}),
[&](auto id){
--id(value);
}
));
}
int main()
{
std::string s = "hello!";
decrement_kindof(s);
assert(s == "hello");
int i = 4;
decrement_kindof(i);
assert(i == 3);
}
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