diff --git a/chapters/chapter_02/CMakeLists.txt b/chapters/chapter_02/CMakeLists.txt index 2bc50d2..6236fdc 100644 --- a/chapters/chapter_02/CMakeLists.txt +++ b/chapters/chapter_02/CMakeLists.txt @@ -1,6 +1,12 @@ add_library( - chapter_02 src/initlist.cpp src/null.cpp src/constexp.cpp src/ifswitch.cpp - src/structured_binding.cpp src/type_inference.cpp) + chapter_02 + src/initlist.cpp + src/null.cpp + src/constexp.cpp + src/ifswitch.cpp + src/structured_binding.cpp + src/type_inference.cpp + src/if_constexpr.cpp) target_compile_features(chapter_02 PUBLIC cxx_std_20) diff --git a/chapters/chapter_02/include/if_constexpr.h b/chapters/chapter_02/include/if_constexpr.h new file mode 100644 index 0000000..f696d16 --- /dev/null +++ b/chapters/chapter_02/include/if_constexpr.h @@ -0,0 +1,9 @@ +#pragma once + +#include "chapter_interface.h" + +class IfConstexprTest : public ChapterTest { +public: + virtual void run() override; + virtual const char *name() const override { return "If constexpr test"; } +}; diff --git a/chapters/chapter_02/src/if_constexpr.cpp b/chapters/chapter_02/src/if_constexpr.cpp new file mode 100644 index 0000000..028084a --- /dev/null +++ b/chapters/chapter_02/src/if_constexpr.cpp @@ -0,0 +1,24 @@ +#include +#include + +#include "if_constexpr.h" + +void print_decltype(auto var) { + std::cout << "variable with value " << var << " is of type "; + + if constexpr (std::is_same::value) { + std::cout << "int"; + } else if constexpr (std::is_same::value) { + std::cout << "double"; + } else { + std::cout << "unknown"; + } + + std::cout << std::endl; +} + +void IfConstexprTest::run() { + print_decltype(23); + print_decltype(23.5); + print_decltype("42"); +} diff --git a/src/main.cpp b/src/main.cpp index 94d49ce..4a567c3 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -4,6 +4,7 @@ #include #include "constexp.h" +#include "if_constexpr.h" #include "ifswitch.h" #include "initlist.h" #include "null.h" @@ -24,6 +25,7 @@ int main(int argc, char **argv) { chapter_2_tests.emplace_back(std::make_unique()); chapter_2_tests.emplace_back(std::make_unique()); chapter_2_tests.emplace_back(std::make_unique()); + chapter_2_tests.emplace_back(std::make_unique()); for (auto &test : chapter_2_tests) { std::cout << "\n" << test->name() << ":" << std::endl;