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From: Michael S <already5chosen@yahoo.com>
Newsgroups: comp.lang.c++
Subject: Re: We have a new standard!
Date: Thu, 2 Jan 2025 17:35:14 +0200
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On Thu, 2 Jan 2025 13:51:53 +0100
David Brown <david.brown@hesbynett.no> wrote:

> 
> Could this all have been done from the start of C++?  In theory, yes
> - in practice no.  std::format and std::print rely on various modern
> C++ features, such as compile-time evaluation of functions, 

It does not look like dependence of std::format on compile-time
evaluation is a requirement of standard rather than implementation
choice of g++ and of clang++.

MSVC 19.30.30706 compiles the following code just fine:

#include <cstdio>
#include <format>

int main(int argc, char** argv)
{
  if (argc >= 3) {
    std::string s = std::format(argv[1], argv[2]);
    printf("%s\n", s.c_str());
  }
  return 0;
}

When run, it produces expected results.

Or, may be, it's because this version of MSVC is not fully C++20
complient.