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f87919b94b
- Define the notion of move-independence, thus relaxing the requirements on accessors. - Rename `members` to `accessors` and use `members` to get the members only - Document the different ways of providing a model - Make the model of Foldable more consistent Fixes #53
146 lines
3.1 KiB
C++
146 lines
3.1 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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#include <boost/hana/assert.hpp>
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#include <boost/hana/map.hpp>
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#include <boost/hana/maybe.hpp>
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#include <boost/hana/pair.hpp>
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#include <boost/hana/string.hpp>
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#include <boost/hana/struct.hpp>
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#include <boost/hana/struct_macros.hpp>
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#include <boost/hana/tuple.hpp>
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#include <string>
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using namespace boost::hana;
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int main() {
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//////////////////////////////////////////////////////////////////////////////
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// Models
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//////////////////////////////////////////////////////////////////////////////
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{
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//! [Comparable]
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struct Person {
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BOOST_HANA_DEFINE_STRUCT(Person,
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(std::string, name),
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(unsigned short, age)
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);
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};
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Person john{"John", 30}, kevin{"Kevin", 20};
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BOOST_HANA_RUNTIME_ASSERT(equal(john, john));
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BOOST_HANA_RUNTIME_ASSERT(not_equal(john, kevin));
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//! [Comparable]
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}{
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//! [Foldable]
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struct Classroom {
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BOOST_HANA_DEFINE_STRUCT(Classroom,
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(unsigned short, boys),
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(unsigned short, girls)
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);
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};
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constexpr Classroom compsci{20, 3}; /* lol */
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BOOST_HANA_CONSTEXPR_ASSERT(
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fold.left(compsci, 0, [](auto total, auto member) {
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// first(member) is the name of the member, here
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// "boys" or "girls", and second(member) is its value.
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return second(member) + total;
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}) == 23
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);
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//! [Foldable]
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}{
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//! [to<Map>]
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struct Person {
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BOOST_HANA_DEFINE_STRUCT(Person,
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(std::string, name),
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(unsigned short, age)
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);
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};
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Person john{"John", 30u};
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BOOST_HANA_RUNTIME_ASSERT(to<Map>(john) == make<Map>(
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make<Pair>(BOOST_HANA_STRING("name"), "John"),
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make<Pair>(BOOST_HANA_STRING("age"), 30u)
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));
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//! [to<Map>]
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}{
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//! [Searchable]
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struct Person {
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BOOST_HANA_DEFINE_STRUCT(Person,
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(std::string, name),
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(unsigned short, age)
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);
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};
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Person john{"John", 30};
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BOOST_HANA_RUNTIME_ASSERT(
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find(john, BOOST_HANA_STRING("name")) == just("John")
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);
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BOOST_HANA_CONSTANT_ASSERT(
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find(john, BOOST_HANA_STRING("foobar")) == nothing
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);
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//! [Searchable]
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}
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//////////////////////////////////////////////////////////////////////////////
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// Methods
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//////////////////////////////////////////////////////////////////////////////
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{
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//! [accessors]
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struct Person {
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BOOST_HANA_DEFINE_STRUCT(Person,
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(std::string, name),
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(unsigned short, age)
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);
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};
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BOOST_HANA_CONSTANT_ASSERT(
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transform(accessors<Person>(), first) == make_tuple(
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BOOST_HANA_STRING("name"), BOOST_HANA_STRING("age")
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)
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);
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auto get_name = second(at_c<0>(accessors<Person>()));
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auto get_age = second(at_c<1>(accessors<Person>()));
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Person john{"John", 30};
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BOOST_HANA_RUNTIME_ASSERT(get_name(john) == "John");
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BOOST_HANA_RUNTIME_ASSERT(get_age(john) == 30);
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//! [accessors]
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}{
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//! [members]
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struct Person {
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BOOST_HANA_DEFINE_STRUCT(Person,
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(std::string, name),
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(unsigned short, age)
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);
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};
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Person john{"John", 30};
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BOOST_HANA_RUNTIME_ASSERT(members(john) == make_tuple("John", 30));
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//! [members]
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}
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}
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