Default C++ standard version to C++20 (#397)

Author: wusatosi

CMakePresets.json

@@ -7,7 +7,7 @@
       "generator": "Ninja",
       "binaryDir": "${sourceDir}/build/${presetName}",
       "cacheVariables": {
-        "CMAKE_CXX_STANDARD": "17",
+        "CMAKE_CXX_STANDARD": "20",
         "CMAKE_CXX_EXTENSIONS": false,
         "CMAKE_CXX_STANDARD_REQUIRED": true,
         "CMAKE_EXPORT_COMPILE_COMMANDS": true,

CONTRIBUTING.md

@@ -43,7 +43,7 @@ that this requires GoogleTest to be installed.
 cmake \
   -B build \
   -S . \
-  -DCMAKE_CXX_STANDARD=17 \
+  -DCMAKE_CXX_STANDARD=20 \
   # Your extra arguments here.
 cmake --build build
 ctest --test-dir build
@@ -73,7 +73,7 @@ Example commands:
 cmake \
   -B build \
   -S . \
-  -DCMAKE_CXX_STANDARD=17 \
+  -DCMAKE_CXX_STANDARD=20 \
   -DCMAKE_TOOLCHAIN_FILE="$VCPKG_ROOT/scripts/buildsystems/vcpkg.cmake"
 cmake --build build
 ctest --test-dir build
@@ -97,7 +97,7 @@ Example commands:
 cmake \
   -B build \
   -S . \
-  -DCMAKE_CXX_STANDARD=17 \
+  -DCMAKE_CXX_STANDARD=20 \
   -DCMAKE_PROJECT_TOP_LEVEL_INCLUDES=./infra/cmake/use-fetch-content.cmake
 cmake --build build
 ctest --test-dir build

cookiecutter/check_cookiecutter.sh

@@ -16,7 +16,7 @@ function stamp() {
         --output-dir "$output_dir" \
         "$cookiecutter_dir" \
         project_name="exemplar" \
-        minimum_cpp_build_version="17" \
+        minimum_cpp_build_version="20" \
         paper="P0898R3" \
         description="A Beman Library Exemplar" \
         unit_test_library="$unit_test_library" \
@@ -60,7 +60,7 @@ function check_templating() {
         --output-dir "$out_dir_path" \
         "$script_dir" \
         project_name="RLZrmX9NfS" \
-        minimum_cpp_build_version="17" \
+        minimum_cpp_build_version="20" \
         paper="P0898R3" \
         description="A Beman Library RLZrmX9NfS" \
         _generating_exemplar="false" \
@@ -70,7 +70,7 @@ function check_templating() {
     local grep_path
     grep_path=$(mktemp)
     grep \
-        --dereference-recursive --context=5 --color=always \
+        -R --context=5 --color=always \
         -e "exemplar" -e "identity" "$out_dir_path/RLZrmX9NfS" > "$grep_path" || true
     rm -rf "$out_dir_path"
     if [[ $(wc -l "$grep_path" | cut -d' ' -f1) -gt 0 ]] ; then

cookiecutter/{{cookiecutter.project_name}}/CONTRIBUTING.md

@@ -73,7 +73,7 @@ Example commands:
 cmake \
   -B build \
   -S . \
-  -DCMAKE_CXX_STANDARD=17 \
+  -DCMAKE_CXX_STANDARD={{cookiecutter.minimum_cpp_build_version}} \
   -DCMAKE_TOOLCHAIN_FILE="$VCPKG_ROOT/scripts/buildsystems/vcpkg.cmake"
 cmake --build build
 ctest --test-dir build