Add support for general integer types in store_into.

include/argparse/argparse.hpp

@@ -698,9 +698,10 @@ class Argument {
     return *this;
   }
 
-  auto &store_into(int &var) {
+  template <typename T, typename std::enable_if<std::is_integral<T>::value>::type * = nullptr>
+  auto &store_into(T &var) {
     if (m_default_value.has_value()) {
-      var = std::any_cast<int>(m_default_value);
+      var = std::any_cast<T>(m_default_value);
     }
     action([&var](const auto &s) {
       var = details::parse_number<int, details::radix_10>()(s);

test/test_store_into.cpp

@@ -27,6 +27,8 @@ TEST_CASE("Test store_into(bool), flag specified" *
   REQUIRE(flag == true);
 }
 
+// int cases
+
 TEST_CASE("Test store_into(int), no default value, non specified" *
           test_suite("store_into")) {
   argparse::ArgumentParser program("test");
@@ -57,6 +59,40 @@ TEST_CASE("Test store_into(int), default value, specified" *
   REQUIRE(res == 5);
 }
 
+// integral cases
+
+TEST_CASE("Test store_into(uint8_t), no default value, non specified" *
+          test_suite("store_into")) {
+  argparse::ArgumentParser program("test");
+  uint8_t res = 55;
+  program.add_argument("--int-opt").store_into(res);
+
+  program.parse_args({"./test.exe"});
+  REQUIRE(res == 55);
+}
+
+TEST_CASE("Test store_into(uint8_t), default value, non specified" *
+          test_suite("store_into")) {
+  argparse::ArgumentParser program("test");
+  uint8_t res = 55;
+  program.add_argument("--int-opt").default_value((uint8_t)3).store_into(res);
+
+  program.parse_args({"./test.exe"});
+  REQUIRE(res == 3);
+}
+
+TEST_CASE("Test store_into(uint8_t), default value, specified" *
+          test_suite("store_into")) {
+  argparse::ArgumentParser program("test");
+  uint8_t res = -1;
+  program.add_argument("--int-opt").default_value((uint8_t)3).store_into(res);
+
+  program.parse_args({"./test.exe", "--int-opt", "5"});
+  REQUIRE(res == 5);
+}
+
+// Double cases
+
 TEST_CASE("Test store_into(double), no default value, non specified" *
           test_suite("store_into")) {
   argparse::ArgumentParser program("test");