stamen

Static Menu Generator

git clone git://git.dimitrijedobrota.com/stamen.git

static.cpp (2108B)

1 #include <cmath> 2 #include <cstddef> 3 #include <format> 4 #include <iostream> 5 #include <limits> 6 7 #include "demo_menu.hpp" 8 9 namespace example { 10 11 int menu_t::visit(const menu_t& menu) 12 { 13 const int sizei = static_cast<int>(menu.items.size()); 14 const size_t dgts = static_cast<size_t>(std::log10(sizei)) + 1; 15 int choice = 0; 16 17 while (true) 18 { 19 std::cout << std::format("{}:\n", menu.title); 20 for (auto i = 0UL; i < menu.items.size(); i++) 21 { 22 std::cout << std::format(" {:{}}. {}\n", i, dgts, menu.items[i].prompt); 23 } 24 25 while (true) 26 { 27 std::cout << "Choose an option: "; 28 if (std::cin >> choice && choice >= -1 && choice < sizei) 29 { 30 if (choice == -1) 31 { 32 std::cout << "Choice: back\n"; 33 return 1; 34 } 35 36 const auto uchoice = static_cast<size_t>(choice); 37 std::cout << "Choice: " << menu.items[uchoice].prompt << "\n\n"; 38 const int res = menu.items[uchoice].callback(uchoice); 39 40 if (res < 2) break; 41 return res - 1; 42 } 43 44 if (std::cin.eof()) 45 { 46 std::cerr << "encountered end of input!\n"; 47 return std::numeric_limits<int>::max(); 48 } 49 50 std::cin.clear(); 51 std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); 52 std::cout << "Invalid option, please choose again!\n"; 53 } 54 55 std::cout << '\n' << std::flush; 56 } 57 58 return 1; 59 } 60 61 int operation1(std::size_t /* unused */) 62 { 63 std::cout << "operation 1\n\n"; 64 std::cout << "Some operation is done\n\n"; 65 std::cout << std::flush; 66 return 1; 67 } 68 69 int operation2(std::size_t /* unused */) 70 { 71 std::cout << "operation 2\n"; 72 std::cout << "Some other operation is done\n"; 73 std::cout << std::flush; 74 return 1; 75 } 76 77 int operation3(std::size_t /* unused */) 78 { 79 std::cout << "operation 3\n"; 80 std::cout << "Yet another operation is done\n"; 81 std::cout << std::flush; 82 return 1; 83 } 84 85 int finish(std::size_t /* unused */) 86 { 87 std::cout << "finishing...\n"; 88 std::cout << std::flush; 89 exit(0); // NOLINT 90 } 91 92 } // namespace example 93 94 int main() 95 { 96 example::menu_main(0); 97 return 0; 98 }