refman-no_resume.md

class no_resume (clause modifier)

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The no_resume modifier indicates that a particular implementation of handle_command in a handler will not need the resumption.

template <typename Cmd>
struct no_resume { };

Usage:

struct Error : command<> { };

class Cancel : public flat_handler<void, no_resume<Error>> {
  void handle_command(Error) override  // no "resumption" argument
  {
    std::cout << "Error!" << std::endl;
  }
};

int main()
{
  std::cout << "Welcome!" << std::endl;
  handle<Cancel>([](){
    std::cout << "So far so good..." << std::endl;
    invoke_command(Error{}); 
    std::cout << "I made it!" << std::endl;
  });
  std::cout << "Bye!" << std::endl;
}

Output:

Welcome!
So far so good...
Error!
Bye!