コンパイル時 FizzBuzz の出力
コンパイル時に FizzBuzz を処理して出力までするのは中３女子の嗜みですよね！
ということでこれを使って、とりあえずコンパイル時にも出力してみた。
Sprout のコードは適当。
[ソース]
#include <boost/preprocessor/repetition/enum.hpp> #include <boost/mpl/print.hpp> #include <sprout/algorithm/transform.hpp> #include <sprout/array.hpp> #include <sprout/string.hpp> #include <sprout/string/alias.hpp> #include <sprout/operation.hpp> #include <sprout/numeric/iota.hpp> #include <sprout/pit.hpp> #include <iostream> template<std::size_t Index, typename String> constexpr char at_c(String const& str){ return Index >= str.length() ? char('\0') : str[Index]; } template<char... cs> struct chars{}; #define STRING_MAX_LENGTH 10 #define DECL_AT_C(z, n, text) \ at_c<n>(text) #define _(str) \ chars<BOOST_PP_ENUM(STRING_MAX_LENGTH, DECL_AT_C, str)> template<typename String, typename Unique> constexpr int print(Unique){ namespace m =boost::mpl; typedef typename m::print<std::tuple<String, Unique>>::type output; return 0; } struct fizzbuzz{ typedef sprout::string<8> result_type; constexpr result_type operator ()(int n) const{ return n % 15 == 0 ? sprout::to_string("FizzBuzz") : n % 3 == 0 ? sprout::to_string("Fizz") : n % 5 == 0 ? sprout::to_string("Buzz") : sprout::realign_to<result_type>(sprout::to_string(n)); } }; int main(){ typedef fizzbuzz::result_type string; static_assert(fizzbuzz()(1) == "1", ""); static_assert(fizzbuzz()(2) == "2", ""); static_assert(fizzbuzz()(3) == "Fizz", ""); static_assert(fizzbuzz()(5) == "Buzz", ""); static_assert(fizzbuzz()(15) == "FizzBuzz", ""); constexpr auto source = sprout::iota( sprout::pit<sprout::array<int, 15> >(), 1 ); constexpr auto result = sprout::transform( source.begin(), source.end(), sprout::pit<sprout::array<string, 15> >(), fizzbuzz() ); // 出力 print<_(result[0])>([]{}); print<_(result[1])>([]{}); print<_(result[2])>([]{}); print<_(result[3])>([]{}); print<_(result[4])>([]{}); print<_(result[5])>([]{}); print<_(result[6])>([]{}); print<_(result[6])>([]{}); print<_(result[7])>([]{}); print<_(result[8])>([]{}); print<_(result[9])>([]{}); print<_(result[10])>([]{}); print<_(result[11])>([]{}); print<_(result[12])>([]{}); print<_(result[13])>([]{}); print<_(result[14])>([]{}); return 0; }
[出力]
In file included from \home\Dropbox\work\software\src\test\cpp\sprout\fizzbuzz3\main.cpp|32| 0: || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'1', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'1', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|80 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'2', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'2', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|81 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|82 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'4', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'4', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|83 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'B', 'u', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'B', 'u', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|84 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|85 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'7', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'7', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|86 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'7', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'7', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|87 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'8', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'8', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|88 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|89 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'B', 'u', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'B', 'u', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|90 col 26| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'1', '1', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'1', '1', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|91 col 27| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'F', 'i', 'z', 'z', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|92 col 27| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'1', '3', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'1', '3', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|93 col 27| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'1', '4', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'1', '4', '\000', '\000', '\000', '\000', '\000', '\000', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|94 col 27| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare] || boost/mpl/print.hpp: In instantiation of 'struct boost::mpl::print<std::tuple<chars<'F', 'i', 'z', 'z', 'B', 'u', 'z', 'z', '\000', '\000'>, main()::<lambda()> > >': main.cpp|39 col 62| required from 'constexpr int print(Unique) [with String = chars<'F', 'i', 'z', 'z', 'B', 'u', 'z', 'z', '\000', '\000'>; Unique = main()::<lambda()>]' main.cpp|95 col 27| required from here boost/mpl/print.hpp|55 col 10| warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
見づらいと思うのは気のせいですよ？
print 関数にラムダ式を渡しているのは2回目以降も出力するためですね。
あと最近また Sprout が暴れているらしいので遊びたい欲が…！
コンパイル時のネタがなにかないかなー。
