How to use the <format> header

问题

In a related question ("std::string formatting like sprintf") I learned about this awesome new C++20 header <format>.

However, there seems to be no supporting compiler. Is this correct or is there a way to use it anyway?
I'm using g++ 9.3 with the -std=c++2a flag and the library <format> is not recognised.

#include <format> // fatal error: format: No such file or directory
#include <iostream>

int main(){
    std::cout << std::format("Hello {}!", "World");
}

g++-9 test.cpp -o test -std=c++2a

回答1:

Use libfmt. The <format> header is essentially a standardized libfmt (with a few small features removed, if I remember correctly).

来源：https://stackoverflow.com/questions/61441494/how-to-use-the-format-header