Merge pull request arximboldi#289 from alex-sparus/remove-cpp20-requirement

Make persist compatible with C++17

Author: arximboldi

doc/persist-introduction.rst

@@ -15,7 +15,7 @@ Dependencies
 ------------
 
 In addition to the `dependencies <introduction.html#dependencies>`_ of
-``immer``, this library makes use of **C++20**, `Boost.Hana
+``immer``, this library makes use of **C++17**, `Boost.Hana
 <https://boostorg.github.io/hana/>`_, `fmt <https://fmt.dev/>`_ and
 `cereal <https://uscilab.github.io/cereal/>`_.
 

extra/fuzzer/persist/CMakeLists.txt

@@ -6,6 +6,8 @@ foreach(_file IN LISTS immer_fuzzers)
   add_executable(${_target} EXCLUDE_FROM_ALL "${_file}")
   set_target_properties(${_target} PROPERTIES OUTPUT_NAME ${_output})
   target_compile_options(${_target} PUBLIC ${immer_fuzzing_engine})
+  target_compile_options(${_target} PRIVATE ${immer_fuzzing_engine}
+                                            -Wno-c++20-designator)
   target_include_directories(${_target} PRIVATE ../..)
   target_link_libraries(${_target} PUBLIC ${immer_fuzzing_engine} immer-dev)
   add_dependencies(fuzzers ${_target})

extra/fuzzer/persist/flex-vector.cpp

@@ -18,7 +18,8 @@
 #include <array>
 
 namespace {
-void require_eq(const auto& a, const auto& b)
+template <class T>
+void require_eq(const T& a, const T& b)
 {
     if (a != b) {
         throw std::runtime_error{

flake.nix

@@ -200,7 +200,7 @@
             "-Dimmer_BUILD_TESTS=ON"
             "-Dimmer_BUILD_PERSIST_TESTS=ON"
             "-Dimmer_BUILD_EXAMPLES=OFF"
-            "-DCXX_STANDARD=20"
+            "-DCXX_STANDARD=17"
           ];
         });
       };

immer/extra/cereal/immer_array.hpp

@@ -10,6 +10,7 @@ void CEREAL_LOAD_FUNCTION_NAME(Archive& ar, immer::array<T, MemoryPolicy>& m)
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;

test/extra/persist/cereal/immer_box.hpp immer/extra/cereal/immer_box.hpptest/extra/persist/cereal/immer_box.hpp renamed to immer/extra/cereal/immer_box.hpp

@@ -33,6 +33,7 @@ CEREAL_LOAD_FUNCTION_NAME(Archive& ar, immer::map<K, T, H, E, MP, B>& m)
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;
@@ -71,6 +72,7 @@ CEREAL_LOAD_FUNCTION_NAME(Archive& ar, immer::map<K, T, H, E, MP, B>& m)
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         K k;

immer/extra/cereal/immer_map.hpp

@@ -16,6 +16,7 @@ void CEREAL_LOAD_FUNCTION_NAME(Archive& ar, immer::set<T, H, E, MP, B>& m)
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;

test/extra/persist/cereal/immer_set.hpp immer/extra/cereal/immer_set.hpptest/extra/persist/cereal/immer_set.hpp renamed to immer/extra/cereal/immer_set.hpp

@@ -17,6 +17,7 @@ void CEREAL_LOAD_FUNCTION_NAME(Archive& ar, immer::table<T, KF, H, E, MP, B>& m)
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;

test/extra/persist/cereal/immer_table.hpp immer/extra/cereal/immer_table.hpptest/extra/persist/cereal/immer_table.hpp renamed to immer/extra/cereal/immer_table.hpp

@@ -15,6 +15,7 @@ void CEREAL_LOAD_FUNCTION_NAME(Archive& ar,
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;
@@ -46,6 +47,7 @@ void CEREAL_LOAD_FUNCTION_NAME(Archive& ar,
 {
     size_type size;
     ar(make_size_tag(size));
+    m = {};
 
     for (auto i = size_type{}; i < size; ++i) {
         T x;