Add utils::RangeToWrapper

library/include/larra/stream_error.hpp

@@ -1,7 +1,7 @@
 #pragma once
 #include <libxml++/libxml++.h>
 
-#include <algorithm>
+#include <larra/utils.hpp>
 #include <nameof.hpp>
 #include <ranges>
 #include <variant>
@@ -23,20 +23,18 @@ constexpr auto ToKebabCaseName() -> std::string_view {
   static constexpr auto rawStr = nameof::nameof_short_type<T>();
 
   constexpr auto str = [] {
-    return rawStr | std::views::transform([](auto ch) {
+    return rawStr  //
-             return impl::IsUpper(ch) ? std::array<char, 2>{'-', impl::ToLower(ch)} : std::array<char, 2>{ch, '\0'};
+           | std::views::transform([](auto ch) {
-           }) |
+               return impl::IsUpper(ch) ? std::array<char, 2>{'-', impl::ToLower(ch)} : std::array<char, 2>{ch, '\0'};
-           std::views::join | std::views::filter([](char ch) {
+             })                //
-             return ch != '\0';
+           | std::views::join  //
-           });
+           | std::views::filter([](char ch) {
+               return ch != '\0';
+             })  //
+           | std::views::drop(1);
   };
-  constexpr auto size = std::ranges::distance(str()) - 1;
+  static constexpr auto arr = str() | std::ranges::to<utils::RangeToWrapper<std::array<char, std::ranges::distance(str())>>>();
-  static constexpr auto arr = [&] {
+  return {arr.data(), arr.size()};
-    std::array<char, size> response;  // NOLINT
-    std::ranges::copy(str() | std::views::drop(1), response.begin());
-    return response;
-  }();
-  return {arr.data(), size};
 }
 
 }  // namespace impl
@@ -53,15 +51,11 @@ struct ErrorImpl : BaseError {
   static inline const auto kKebabCaseName = static_cast<std::string>(impl::ToKebabCaseName<T>());
 
   static constexpr auto kErrorMessage = [] -> std::string_view {
+    static constexpr auto name = nameof::nameof_short_type<T>();
     static constexpr auto str = [] {
-      return std::array{std::string_view{"Stream Error: "}, nameof::nameof_short_type<T>(), std::string_view{"\0", 1}} | std::views::join;
+      return std::array{std::string_view{"Stream Error: "}, std::string_view{name}, std::string_view{"\0", 1}} | std::views::join;
     };
-    constexpr auto size = std::ranges::distance(str());
+    static constexpr auto array = str() | std::ranges::to<utils::RangeToWrapper<std::array<char, std::ranges::distance(str())>>>();
-    static constexpr auto array = [&] {
-      std::array<char, size> response;  // NOLINT
-      std::ranges::copy(str(), response.begin());
-      return response;
-    }();
     return {array.data(), array.size() - 1};
   }();
   static constexpr auto TryParse(xmlpp::Element* element) -> std::optional<T> {

library/include/larra/utils.hpp

@@ -267,4 +267,32 @@ inline auto StartLifetimeAs(const void* ptr) -> const T* {
 
 #endif
 
+// Example: "Hello" | std::ranges::to<RangeToWrapper<std::array<char, 6>>>()
+template <typename T>
+struct RangeToWrapper : T {
+  [[nodiscard]] constexpr auto Base() & -> decltype(auto) {
+    return static_cast<T&>(*this);
+  }
+  [[nodiscard]] constexpr auto Base() const& -> decltype(auto) {
+    return static_cast<const T&>(*this);
+  }
+  [[nodiscard]] constexpr auto Base() && -> decltype(auto) {
+    return static_cast<T&&>(*this);
+  }
+  [[nodiscard]] constexpr auto Base() const&& -> decltype(auto) {
+    return static_cast<const T&&>(*this);
+  }
+  template <typename Range>  // NOLINTNEXTLINE
+  constexpr RangeToWrapper(std::from_range_t, Range&& range) {
+    auto result = std::ranges::copy(range, this->begin());
+    if(result.in != std::ranges::end(range) || result.out != std::ranges::end(*this)) {
+      throw std::invalid_argument{"Invalid range size"};
+    }
+  }
+  template <typename... Args>  // NOLINTNEXTLINE
+  constexpr RangeToWrapper(Args&&... args)
+    requires requires { T{std::forward<Args>(args)...}; }
+      : T{std::forward<Args>(args)...} {};
+};
+
 }  // namespace larra::xmpp::utils