Refactor nit-* cli main functions with guards

Guard from escaping exceptions,
and properly handle command-line option errors.

Issue #11
Issue #9

cli/guard.h

@@ -0,0 +1,31 @@
+#include <exception>
+#include <iostream>
+
+#include <boost/exception/all.hpp>
+
+#include <nit/error.h>
+
+/// Guards a main function from exceptions.
+///
+/// @tparam T  Function type returning integer code.
+///
+/// @param[in] runner  The body of the main function.
+///
+/// @returns The return of the runner if no exceptions are encountered.
+///          1 if an exception is encountered.
+template <class T>
+int guard(T&& runner) noexcept {
+  try {
+    return runner();
+  } catch (const nit::Error& nit_err) {
+    std::cerr << boost::diagnostic_information(nit_err);
+    return 1;
+  } catch (const boost::exception& boost_err) {
+    std::cerr << "Unexpected Boost Exception:\n"
+              << boost::diagnostic_information(boost_err);
+    return 1;
+  } catch (const std::exception& err) {
+    std::cerr << "Unexpected Exception:\n" << err.what();
+    return 1;
+  }
+}

cli/nit-colex.cc

@@ -1,14 +1,16 @@
+#include <exception>
 #include <iostream>
 #include <string>
 #include <vector>
 
-#include <boost/format.hpp>
 #include <boost/program_options.hpp>
 
 #include <nit/eval/card.h>
 #include <nit/eval/card_set.h>
 #include <nit/util/combinations.h>
 
+#include "guard.h"
+
 namespace po = boost::program_options;
 
 #if 0
@@ -30,66 +32,66 @@ expandRankSet(size_t numCards)
 }
 #endif
 
-int main(int argc, char** argv) {
+namespace {
+
+int runColex(int argc, char** argv) {
+  // set up the program options, handle the help case, and extract the values.
+  po::options_description desc(
+      "nit-colex, a utility which prints all combinations "
+      "of poker hands, using canonical suits, or only ranks");
+
+  // clang-format off
+  desc.add_options()
+      ("help,?", "produce help message")
+      ("num-cards,n", po::value<std::size_t>()->default_value(2),
+       "number of cards in hands")
+      ("ranks", "print the set of rank values");
+  // clang-format on
+
+  po::variables_map vm;
   try {
-    // set up the program options, handle the help case, and extract the
-    // values
-    po::options_description desc(
-        "nit-colex, a utility which prints all combinations "
-        "of poker hands, using canonical suits, or only ranks");
-
-    // clang-format off
-    desc.add_options()
-        ("help,?", "produce help message")
-        ("num-cards,n", po::value<std::size_t>()->default_value(2),
-            "number of cards in hands")
-        ("ranks", "print the set of rank values");
-    // clang-format on
-
-    po::variables_map vm;
-    po::store(po::command_line_parser(argc, argv)
-                  .style(po::command_line_style::unix_style)
-                  .options(desc)
-                  .run(),
-              vm);
-    po::notify(vm);
-
-    // check for help
-    if (vm.count("help") || argc == 1) {
-      std::cout << desc << std::endl;
-      return 1;
+    po::store(po::parse_command_line(argc, argv, desc), vm);
+  } catch (const std::exception& err) {
+    std::cerr << "Option error: " << err.what() << "\n\n" << desc << std::endl;
+    return 1;
+  }
+  po::notify(vm);
+
+  // check for help
+  if (vm.count("help") || argc == 1) {
+    std::cout << desc << std::endl;
+    return 1;
+  }
+
+  // extract the options
+  std::size_t num_cards = vm["num-cards"].as<std::size_t>();
+
+  std::set<nit::CardSet> canonicalHands;
+  std::map<std::string, std::size_t> rankHands;
+  nit::combinations cards(52, num_cards);
+  do {
+    nit::CardSet hand;
+    for (std::size_t i = 0; i < num_cards; i++) {
+      hand.insert(nit::Card(cards[i]));
     }
+    canonicalHands.insert(hand.canonize());
+    rankHands[hand.rankstr()] = hand.rankColex();
+  } while (cards.next());
 
-    // extract the options
-    std::size_t num_cards = vm["num-cards"].as<std::size_t>();
-
-    std::set<nit::CardSet> canonicalHands;
-    std::map<std::string, std::size_t> rankHands;
-    nit::combinations cards(52, num_cards);
-    do {
-      nit::CardSet hand;
-      for (std::size_t i = 0; i < num_cards; i++) {
-        hand.insert(nit::Card(cards[i]));
-      }
-      canonicalHands.insert(hand.canonize());
-      rankHands[hand.rankstr()] = hand.rankColex();
-    } while (cards.next());
-
-    if (vm.count("ranks") > 0) {
-      for (auto& rankHand : rankHands)
-        std::cout << boost::format("%s: %d\n") % rankHand.first %
-                         rankHand.second;
-    } else {
-      for (const auto& canonicalHand : canonicalHands)
-        std::cout << boost::format("%s: %d\n") % canonicalHand.str() %
-                         canonicalHand.colex();
+  if (vm.count("ranks") > 0) {
+    for (auto& rankHand : rankHands)
+      std::cout << rankHand.first << ": " << rankHand.second << '\n';
+  } else {
+    for (const auto& canonicalHand : canonicalHands) {
+      std::cout << canonicalHand.str() << ": " << canonicalHand.colex() << '\n';
     }
-  } catch (std::exception& e) {
-    std::cerr << "-- caught exception--\n" << e.what() << "\n";
-    return 1;
-  } catch (...) {
-    std::cerr << "Exception of unknown type!\n";
-    return 1;
   }
+
   return 0;
 }
+
+}  // namespace
+
+int main(int argc, char** argv) {
+  return guard([&argc, &argv] { return runColex(argc, argv); });
+}

cli/nit-eval.cc

@@ -1,3 +1,4 @@
+#include <exception>
 #include <iostream>
 #include <string>
 #include <vector>
@@ -6,16 +7,20 @@
 
 #include <nit/enum/showdown_enumerator.h>
 
+#include "guard.h"
+
 namespace po = boost::program_options;
 
-int main(int argc, char** argv) {
+namespace {
+
+int runEval(int argc, char** argv) {
   po::options_description desc("nit-eval, a poker hand evaluator");
 
   // clang-format off
   desc.add_options()
       ("help,?", "produce help message")
       ("game,g", po::value<std::string>()->default_value("h"),
-          "game to use for evaluation")
+       "game to use for evaluation")
       ("board,b", po::value<std::string>(), "community cards for he/o/o8")
       ("hand,h", po::value<std::vector<std::string>>(), "a hand for evaluation")
       ("quiet,q", "produces no output");
@@ -26,12 +31,13 @@ int main(int argc, char** argv) {
   p.add("hand", -1);
 
   po::variables_map vm;
-  po::store(po::command_line_parser(argc, argv)
-                .style(po::command_line_style::unix_style)
-                .options(desc)
-                .positional(p)
-                .run(),
-            vm);
+  try {
+    po::store(po::parse_command_line(argc, argv, desc), vm);
+  } catch (const std::exception& err) {
+    std::cerr << "Option error: " << err.what() << "\n\n"
+              << desc << std::endl;
+    return 1;
+  }
   po::notify(vm);
 
   // check for help
@@ -81,4 +87,12 @@ int main(int argc, char** argv) {
                 << results[i].str() << ")" << std::endl;
     }
   }
+
+  return 0;
+}
+
+}  // namespace
+
+int main(int argc, char** argv) {
+  return guard([&argc, &argv] { return runEval(argc, argv); });
 }