Compile Time C++ Snake Game

Implementation of Snake / Nibbler using C++14 template metaprogramming. All the logic is implemented at compile time. When the program is run, it prints out the result of gameplay. Here's a post covering the implementation in more detail.

Two versions are included:

• An "interactive" game that saves state between compiler runs. Each compile advances one turn. Found on the interactive branch.
• A static version that plays the entire game in a single compile. This is the version on the main branch.

Interactive

Plays one step of the game every time the game is recompiled. Uses compiler flags to control input:

$ clang++ -std=c++1y main.cpp -D COMMAND -o snake ; ./snake

Valid commands are UP, DOWN, LEFT, and RIGHT. If no command is entered, the snake will go straight. You can reset to the original state by running ./reset.sh.

bash-3.2$ ./reset.sh 
bash-3.2$ clang++ -std=c++1y main.cpp  -o snake ; ./snake
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺▶*╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -D RIGHT -o snake ; ./snake
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺*╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺▶▶╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -o snake ; ./snake
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺*╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺▶▶╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -D UP -o snake ; ./snake
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺*╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▶╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -o snake ; ./snake
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▶╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -o snake ; ./snake
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -D RIGHT -o snake ; ./snake
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲▶╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -o snake ; ./snake
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲▶▶
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
bash-3.2$ clang++ -std=c++1y main.cpp -o snake ; ./snake
-- You Are Dead --
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲▶█
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺

Static

Plays the entire game in a single compiler run. This code is on the main branch.

int main(int argc, const char* argv[])
{
    using inputs = PlayerInput<
        Input::Right, Input::Up, Input::None, Input::Right, Input::Up,
        Input::None, Input::None, Input::Left, Input::None, Input::None,
        Input::None, Input::None, Input::None, Input::Down, Input::None,
        Input::None, Input::None, Input::None, Input::None, Input::None,
        Input::None, Input::Right, Input::Up, Input::Left>;

    using state = InitialState;
    
    using game = play_t<inputs, state>;

    Printer<game>::Print(std::cout);
    
    return 0;
}

------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺▶*╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺*╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺▶▶╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺*╺╺
╺╺╺╺╺╺▲╺╺╺
╺╺╺╺╺╺▶╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺▲*╺╺
╺╺╺╺╺╺▲╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺▲▶╺╺
╺╺╺╺╺╺▲╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺▲▶╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▶╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺╺◀▲╺╺
╺╺╺╺╺╺╺▲╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺╺◀◀▲╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺╺◀◀◀╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*╺◀◀◀╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺*◀◀◀╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺◀◀◀◀╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺◀◀◀╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺◀◀╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺◀╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺╺*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼*╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
*╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼▶╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------------------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
*╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
╺▼▲╺╺╺╺╺╺╺
╺▼▶╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
------ dead ------
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
*╺╺╺╺╺╺╺╺╺
╺╺╺╺╺╺╺╺╺╺
╺▼╺╺╺╺╺╺╺╺
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╺╺╺╺╺╺╺╺╺╺
Program ended with exit code: 0