Monster

Advanced C++ Template MetaProgramming Framework

Overview

cpp
#include <cstdint>
#include <monster.hpp>

using namespace monster;

int main(int argc, char* argv[])
{
    // arrange the same elements adjacent in a sequence, keep the relative order
    using a1 = adjacent_t<std::tuple<char, double, char, int, double>>;
    using a2 = adjacent_t<std::index_sequence<4, 3, 0, 3, 2, 4, 5, 3>>;

    static_assert(std::is_same_v<a1, std::tuple<char, char, double, double, int>>);
    static_assert(std::is_same_v<a2, std::index_sequence<4, 4, 3, 3, 3, 0, 2, 5>>);

    // Boyer-Moore-Horspool (BMH) algorithm searches for occurrences of a sequence within another sequence
    using b1 = bmh_t<std::tuple<int, char, int>, std::tuple<int, int, char, int, char, int, char, int>>;
    using b2 = bmh_t<std::integer_sequence<int, 7, 5>, std::integer_sequence<int, 7, 5, 4, 0, 7, 5, 9>>;

    static_assert(std::is_same_v<b1, std::index_sequence<1, 3, 5>>);
    static_assert(std::is_same_v<b2, std::index_sequence<0, 4>>);

    // Knuth–Morris–Pratt (KMP) algorithm searches for occurrences of a sequence within another sequence
    using k1 = kmp_t<std::tuple<int, char, int>, std::tuple<int, int, char, int, char, int, char, int>>;
    using k2 = kmp_t<std::integer_sequence<int, 7, 5>, std::integer_sequence<int, 7, 5, 4, 0, 7, 5, 9>>;

    static_assert(std::is_same_v<k1, std::index_sequence<1, 3, 5>>);
    static_assert(std::is_same_v<k2, std::index_sequence<0, 4>>);

    // find K-th smallest element in a sequence (k == 2)
    using min1 = select_t<2, std::tuple<short, int, double, int, char>>;
    using min2 = select_t<2, std::integer_sequence<int, -2, 1, 0, -7, 4, 3>>;

    static_assert(std::is_same_v<min1, short>);
    static_assert(std::is_same_v<min2, c_<-2>>);

    // find K-th greatest element in a sequence (k == 2)
    using max1 = select_t<2, std::tuple<short, int, double, int, char>, greater_equal_t>;
    constexpr auto max2 = select_v<2, std::integer_sequence<int, -2, 1, 0, -7, 4, 3>, greater_equal_t>;

    static_assert(std::is_same_v<max1, int>);
    static_assert(max2 == 3);

    // returns element at specific index of a sequence
    using e1 = element_t<1, std::tuple<char, double, int>>;
    using e2 = element_t<3, std::integer_sequence<int, 1, -2, 7, 4>>;

    constexpr auto e3 = element_v<3, std::integer_sequence<int, 1, -2, 7, 4>>;

    static_assert(std::is_same_v<e1, double>);
    static_assert(std::is_same_v<e2, c_4>);

    static_assert(e3 == 4);

    // remove duplicate elements from a sequence, keep the first appearance
    using u1 = unique_t<std::tuple<int, char, int, double>>;
    using u2 = unique_t<std::integer_sequence<int, 2, 2, 3, 4, 3>>;

    static_assert(std::is_same_v<u1, std::tuple<int, char, double>>);
    static_assert(std::is_same_v<u2, std::integer_sequence<int, 2, 3, 4>>);

    // swap elements at specific index of a sequence
    using s1 = swap_t<1, 3, std::tuple<int, double, char, float>>;
    using s2 = swap_t<0, 2, std::integer_sequence<int, 1, -2, 7, 4>>;

    static_assert(std::is_same_v<s1, std::tuple<int, float, char, double>>);
    static_assert(std::is_same_v<s2, std::integer_sequence<int, 7, -2, 1, 4>>);

    // sort elements by value in a sequence
    using s3 = quick_sort_t<std::tuple<double, short, double, int, char, char, double>>;
    using s4 = quick_sort_t<std::integer_sequence<int, 2, 1, 0, -3, 4, 1, -7, 5, -2>>;

    static_assert(std::is_same_v<s3, std::tuple<char, char, short, int, double, double, double>>);
    static_assert(std::is_same_v<s4, std::integer_sequence<int, -7, -3, -2, 0, 1, 1, 2, 4, 5>>);

    // sort elements by index in a sequence
    using s5 = sort_index_t<std::tuple<double, short, double, int, char, char, double>>;
    using s6 = sort_index_t<std::integer_sequence<int, 2, 1, 0, -3, 4, 1, -7, 5, -2>>;

    static_assert(std::is_same_v<s5, std::index_sequence<4, 5, 1, 3, 6, 2, 0>>);
    static_assert(std::is_same_v<s6, std::index_sequence<6, 3, 8, 2, 1, 5, 0, 4, 7>>);

    // reverses the order of the elements of a sequence
    using r1 = reverse_t<std::tuple<float, double, int, short>>;
    using r2 = reverse_t<std::integer_sequence<int, 1, 0, 2, -2, 7, 6>>;

    static_assert(std::is_same_v<r1, std::tuple<short, int, double, float>>);
    static_assert(std::is_same_v<r2, std::integer_sequence<int, 6, 7, -2, 2, 0, 1>>);

    // reverses the order of the elements of a sequence recursively
    using r3 = reverse_recursive_t<std::tuple<int, std::tuple<int, std::tuple<char, short>>, char>>;
    using r4 = reverse_recursive_t<std::tuple<char, std::integer_sequence<int, 7, 2, 0, 4, 8>, int>>;

    static_assert(std::is_same_v<r3, std::tuple<char, std::tuple<std::tuple<short, char>, int>, int>>);
    static_assert(std::is_same_v<r4, std::tuple<int, std::integer_sequence<int, 8, 4, 0, 2, 7>, char>>);

    // rotates the elements in the range [begin, middle, end) of a sequence
    using r5 = rotate_t<0, 2, 5, std::tuple<int, char, double, float, int64_t>>;
    using r6 = rotate_t<2, 4, 7, std::integer_sequence<int, 9, 8, 1, 2, 3, 4, 5, 7, 6>>;

    static_assert(std::is_same_v<r5, std::tuple<double, float, int64_t, int, char>>);
    static_assert(std::is_same_v<r6, std::integer_sequence<int, 9, 8, 3, 4, 5, 1, 2, 7, 6>>);

    // returns the elements in the range [begin, end) of a sequence
    using r7 = range_t<1, 5, std::tuple<int, char, float, double, int, short>>;
    using r8 = range_t<2, 6, std::integer_sequence<int, 1, 2, -2, 4, 3, 5, 8, -5>>;

    static_assert(std::is_same_v<r7, std::tuple<char, float, double, int>>);
    static_assert(std::is_same_v<r8, std::integer_sequence<int, -2, 4, 3, 5>>);

    return 0;
}

Introduction

Monster is a metaprogramming library, which is header-only, extensible and modern C++ oriented.
It exhibits a form of pure type programming of compile-time algorithms, sequences and Higher-Order Metafunctions.

Monster provides a conceptual foundation and an extensive set of powerful and coherent tools, that
makes doing explict advanced Template MetaProgramming (TMP) in modern C++ easy and enjoyable.

Compiler requirements

The library relies on a C++20 compiler and standard library, but nothing else is required.

More specifically, Monster requires a compiler/standard library supporting the following C++20 features (non-exhaustively):

concepts
lambda templates
All the C++20 type traits from the <type_traits> header

Building

Monster is header-only. To use it just add the necessary #include line to your source files, like this:

cpp
#include <monster.hpp>

To build the example with cmake, cd to the root of the project and setup the build directory:

bash
mkdir build
cd build
cmake ..

Make and install the executables:

make -j4
make install

The executables are now located at the bin directory of the root of the project.
The example can also be built with the script build.sh, just run it, the executables will be put at the /tmp directory.

Documentation

You can browse the documentation online at Guidelines.md.
The documentation covers everything you should need including installing the library,
a table of contents, and an extensive reference section with examples.