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73 lines
1.6 KiB
C++
73 lines
1.6 KiB
C++
/*
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@copyright Louis Dionne 2015
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
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*/
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// Make sure assert always triggers an assertion
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#ifdef NDEBUG
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# undef NDEBUG
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#endif
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#include <cassert>
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#include <iostream>
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#include <string>
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#include <tuple>
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#include <type_traits>
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#include <boost/hana/ext/std/type_traits.hpp>
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//! [includes]
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#include <boost/hana.hpp>
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using namespace boost::hana;
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//! [includes]
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int main() {
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// IMPORTANT NOTE:
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// When changing this, make sure the corresponding changes are propagated
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// to `example/tutorial/amphi.cpp`.
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//! [decls]
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struct Person { std::string name; };
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struct Car { std::string name; };
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struct City { std::string name; };
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//! [decls]
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//! [make_tuple]
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auto stuff = make_tuple(Person{"Louis"}, Car{"Toyota"}, City{"Quebec"});
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//! [make_tuple]
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{
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//! [_tuple]
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_tuple<Person, Car, City> stuff{Person{"Louis"}, Car{"Toyota"}, City{"Quebec"}};
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//! [_tuple]
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}
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//! [basic_operations]
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Car& car = at_c<1>(stuff);
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assert(car.name == "Toyota");
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static_assert(length(stuff) == 3u, "");
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//! [basic_operations]
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//! [transform]
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_tuple<std::string, std::string, std::string> names = transform(stuff, [](auto x) { return x.name; });
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assert(names == make_tuple("Louis", "Toyota", "Quebec"));
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//! [transform]
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//! [metafunction]
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using namespace traits; // bring in remove_cv and add_pointer
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auto F = [](auto T) { // F is a "metafunction"; just pretend T is a type
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return add_pointer(remove_cv(T));
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};
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//! [metafunction]
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//! [type]
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auto intp = F(type<int const>);
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static_assert(intp == type<int*>, "");
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//! [type]
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}
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