![]() |
Home | Libraries | People | FAQ | More |
![]() |
Caution |
---|---|
C++20 PFR module support is on early stage, targets, flags and behavior may change in the future |
If using modern CMake define CMake option -DPFR_USE_MODULES=1
to build a C++20 module and make the pfr::pfr
CMake target provide it. After that an explicit usage of C++20 module pfr
is allowed:
#include <iostream> #include <iomanip> #include <string> import pfr; struct some_person { std::string name; unsigned birth_year; }; int main() { some_person val{"Edgar Allan Poe", 1809}; std::cout << pfr::get<0>(val) // No macro! << " was born in " << pfr::get<1>(val); // Works with any aggregate! std::cout << '\n' << pfr::io(val); // Outputs: {"Edgar Allan Poe", 1809} std::cout << "\n." << pfr::get_name<0, some_person>() << '=' << val.name << '\n'; // Outputs: .name=Edgar Allan Poe }
The pfr::pfr
CMake target gives an ability to mix
includes and imports of the PFR library in different translation units. Moreover,
if PFR_USE_MODULES
macro is
defined then all the pfr/...
includes implicitly do import pfr;
to give
all the benifits of modules without changing the existing code.
![]() |
Note |
---|---|
For better compile times make sure that |
If not using CMake, then the module could be build manually from the modules/pfr.cppm
file.
For manual module build the following commands can be used for clang compiler:
cd pfr/module clang++ -I ../include -std=c++20 --precompile -x c++-module pfr.cppm
After that, the module could be used in the following way:
clang++ -std=c++20 -fmodule-file=pfr.pcm pfr.pcm usage_sample.cpp