feat: return message as a string view (#95)

* feat: modify `Error::message` to return `std::string_view`

* build: set `CMAKE_CXX_STANDARD` to `17`

Author: threeal

CMakeLists.txt

@@ -6,6 +6,9 @@ if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
   set(NOT_SUBPROJECT TRUE)
 endif()
 
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
 # Initialize CPM.cmake
 include(cmake/CPM.cmake)
 

include/errors/error.hpp

@@ -3,6 +3,7 @@
 #include <memory>
 #include <ostream>
 #include <string>
+#include <string_view>
 #include <utility>
 
 namespace errors {
@@ -27,7 +28,7 @@ class Error {
    * std::cout << err << std::endl;
    * @endcode
    */
-  std::string message() const;
+  std::string_view message() const;
 
   friend Error make(const std::string& msg);
 

src/error.cpp

@@ -4,7 +4,7 @@ namespace errors {
 
 Error::Error(const std::shared_ptr<const std::string>& message_ptr) : message_ptr(message_ptr) {}
 
-std::string Error::message() const {
+std::string_view Error::message() const {
   if (!message_ptr) return "no error";
   return *message_ptr;
 }