The C++11 way to separate the parts of a user-defined numeric (integer or floating point) literal with ' as e.g. in 1'500ms stalls parsing for syntax highlighting. I couldn't find anything on the net about this - my new team makes heavy use of this and I am the only Emacs user, so it is me who has to adapt. Is there a way to make the parser for C++ recognize the new syntax without too much hassle? See also: https://en.cppreference.com/w/cpp/language/user_literal

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What version of emacs do you use? I'm not able to reproduce the problem in Emacs 27.1, using this test program:

#include <iostream>
#include <chrono>

int main()
    using namespace std::chrono;
    std::chrono::milliseconds t = 1'234ms;
    std::cout << t.count() << '\n';
  • You are correct. 26.3 didn't yet handle them correctly. Jan 28, 2021 at 11:36

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