add optional interface to result type

hanickadot · Jan 24, 2024 · 132cea5 · 132cea5
1 parent 6d9fa80
commit 132cea5
Showing 1 changed file with 66 additions and 7 deletions.
diff --git a/include/ctre/return_type.hpp b/include/ctre/return_type.hpp
@@ -8,6 +8,7 @@
 #include <string_view>
 #include <string>
 #include <iterator>
+#include <optional>
 #ifdef _MSC_VER
 #include <memory>
 #endif
@@ -127,6 +128,14 @@ template <size_t Id, typename Name = void> struct captured_content {
 			std::from_chars(view.data(), view.data() + view.size(), result, std::forward<Ts>(args)...);
 			return result;
 		}
+
+		template <typename R = int, typename... Ts> constexpr CTRE_FORCE_INLINE auto to_optional_number(Ts && ... args) const noexcept -> std::optional<R> {
+			if (!static_cast<bool>(*this)) {
+				return std::nullopt;
+			}
+
+			return to_number<R>(std::forward<Ts>(args)...);
+		}
 #endif
 
 		template <typename It = Iterator> constexpr CTRE_FORCE_INLINE auto to_view() const noexcept {
@@ -138,6 +147,17 @@ template <size_t Id, typename Name = void> struct captured_content {
 			return std::basic_string_view<char_type>(data_unsafe(), static_cast<size_t>(unit_size()));
 		}
 
+		constexpr CTRE_FORCE_INLINE auto view() const noexcept {
+			return to_view();
+		}
+
+		template <typename It = Iterator> constexpr CTRE_FORCE_INLINE auto to_optional_view() const noexcept -> std::optional<std::basic_string_view<char_type>> {
+			if (!static_cast<bool>(*this)) {
+				return std::nullopt;
+			}
+			return to_view();
+		}
+
 		constexpr CTRE_FORCE_INLINE std::basic_string<char_type> to_string() const noexcept {
 			#if __cpp_char8_t >= 201811
 			if constexpr (std::is_same_v<Iterator, utf8_iterator>) {
@@ -150,11 +170,14 @@ template <size_t Id, typename Name = void> struct captured_content {
 			#endif
 		}
 
-		constexpr CTRE_FORCE_INLINE auto view() const noexcept {
-			return to_view();
+		constexpr CTRE_FORCE_INLINE auto str() const noexcept {
+			return to_string();
 		}
 
-		constexpr CTRE_FORCE_INLINE auto str() const noexcept {
+		template <typename It = Iterator> constexpr CTRE_FORCE_INLINE auto to_optional_string() const noexcept -> std::optional<std::basic_string<char_type>> {
+			if (!static_cast<bool>(*this)) {
+				return std::nullopt;
+			}
 			return to_string();
 		}
 
@@ -166,6 +189,14 @@ template <size_t Id, typename Name = void> struct captured_content {
 			return to_string();
 		}
 
+		constexpr CTRE_FORCE_INLINE operator std::optional<std::basic_string_view<char_type>>() const noexcept {
+			return to_optional_view();
+		}
+
+		constexpr CTRE_FORCE_INLINE explicit operator std::optional<std::basic_string<char_type>>() const noexcept {
+			return to_optional_string();
+		}
+
 		constexpr CTRE_FORCE_INLINE static size_t get_id() noexcept {
 			return Id;
 		}
@@ -378,6 +409,7 @@ template <typename Iterator, typename... Captures> class regex_results {
 		return bool(_captures.template select<0>());
 	}
 
+	// implicit conversions
 	constexpr CTRE_FORCE_INLINE operator std::basic_string_view<char_type>() const noexcept {
 		return to_view();
 	}
@@ -386,28 +418,55 @@ template <typename Iterator, typename... Captures> class regex_results {
 		return to_string();
 	}
 
+	constexpr CTRE_FORCE_INLINE operator std::optional<std::basic_string_view<char_type>>() const noexcept {
+		return to_optional_view();
+	}
+
+	constexpr CTRE_FORCE_INLINE explicit operator std::optional<std::basic_string<char_type>>() const noexcept {
+		return to_optional_string();
+	}
+
+	// conversion to numbers
 #if __has_include(<charconv>)
 	template <typename R = int, typename... Ts> constexpr CTRE_FORCE_INLINE auto to_number(Ts && ... args) const noexcept -> R {
 		return _captures.template select<0>().template to_number<R>(std::forward<Ts>(args)...);
 	}
+
+	template <typename R = int, typename... Ts> constexpr CTRE_FORCE_INLINE auto to_optional_number(Ts && ... args) const noexcept -> std::optional<R> {
+		return _captures.template select<0>().template to_optional_number<R>(std::forward<Ts>(args)...);
+	}
 #endif
 
+	// conversion to basic_string_view
 	constexpr CTRE_FORCE_INLINE auto to_view() const noexcept {
 		return _captures.template select<0>().to_view();
 	}
 
+	constexpr CTRE_FORCE_INLINE auto view() const noexcept {
+		return _captures.template select<0>().view(); // this should be deprecated (??)
+	}
+
+	constexpr CTRE_FORCE_INLINE auto to_optional_view() const noexcept {
+		return _captures.template select<0>().to_optional_view();
+	}
+
+	// conversion to basic_string
 	constexpr CTRE_FORCE_INLINE auto to_string() const noexcept {
 		return _captures.template select<0>().to_string();
 	}
 
-	constexpr CTRE_FORCE_INLINE auto view() const noexcept {
-		return _captures.template select<0>().view();
+	constexpr CTRE_FORCE_INLINE auto str() const noexcept {
+		return _captures.template select<0>().to_string();  // this should be deprecated (??)
 	}
 
-	constexpr CTRE_FORCE_INLINE auto str() const noexcept {
-		return _captures.template select<0>().to_string();
+	constexpr CTRE_FORCE_INLINE auto to_optional_string() const noexcept {
+		return _captures.template select<0>().to_optional_string();
 	}
 
+
+
+
+
 	constexpr CTRE_FORCE_INLINE size_t size() const noexcept {
 		return _captures.template select<0>().size();
 	}