tweaks to compile

CMakeLists.txt

@@ -4,7 +4,7 @@
 
 cmake_minimum_required(VERSION 4.1.2)
 
-project(project_name_here
+project(psl
     VERSION 0.1
     LANGUAGES CXX)
 
@@ -25,7 +25,3 @@ set(CMAKE_CXX_FLAGS "-Wall -pedantic -Wextra -Wfloat-equal -Wundef -Wpointer-ari
 
 # lib src code
 add_subdirectory(src)
-
-# app source code
-add_subdirectory(apps)
-

apps/CMakeLists.txt

@@ -1,8 +0,0 @@
-# based heavily on https://gitlab.com/CLIUtils/modern-cmake/-/blob/master/examples/extended-project/apps/CMakeLists.txt
-
-add_executable(exe_name exe_entry.cpp)
-
-# example library link
-#target_link_libraries(exe_name fmt::fmt)
-
-target_compile_features(exe_name PRIVATE cxx_std_20)

apps/exe_entry.cpp

@@ -1,4 +0,0 @@
-int main(void){
-    
-    return 0;
-}

include/visiting.h

@@ -0,0 +1,18 @@
+
+namespace psl {
+
+/// usage:
+/// const auto visitor = overloads {
+///     [](type_1 v){...},
+///     [](type_2 v){...},
+///     ...
+/// };
+/// visitor will then be an object with an overloaded function call op
+/// which accepts type_1, type_2, etc
+/// got this code from https://en.cppreference.com/w/cpp/utility/variant/visit
+/// seems to need C++20 to work but haven't researched to double check
+template <class... Ts> struct overloads : Ts... {
+  using Ts::operator()...;
+};
+
+} // namespace psl

src/CMakeLists.txt

@@ -1,17 +1,16 @@
 # based heavily on https://gitlab.com/CLIUtils/modern-cmake/-/blob/master/examples/extended-project/src/CMakeLists.txt
 
-# example from when I was doing raft cpp impl
-#set(HEADER_LIST "${raft_cpp_impl_SOURCE_DIR}/include/raft/lib.hpp")
+set(HEADER_LIST "${psl_SOURCE_DIR}/include/visiting.h")
 
-add_library(example_lib lib.cpp ${HEADER_LIST})
+add_library(psl lib.cpp ${HEADER_LIST})
 
 # We need this directory, and users of our library will need it too
-target_include_directories(example_lib PUBLIC ../include)
+target_include_directories(psl PUBLIC ../include)
 
 
 #target_link_libraries(example_lib PRIVATE Boost::boost)
 
-target_compile_features(example_lib PUBLIC cxx_std_17)
+target_compile_features(psl PUBLIC cxx_std_20)
 
 # IDEs should put the headers in a nice place
 source_group(