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// test of function object as default parameter.
// c++ -Wall -std=c++11 ./funcobj_param_test.cpp  -o funcobj_param_test
// 
// $ ./funcobj_param_test
// call func
// call callback func
// arg1: str1
// arg2: str2
// call func
#include <iostream>
#include <functional>
#include <string>

// typedef
using cbfunc_t = std::function<void(std::string arg1, std::string arg2)>;

void func(cbfunc_t cb = [](std::string msg, std::string str2) {}) {
  std::string str1("str1");
  std::string str2("str2");

  std::cout << "call func" << std::endl;
  cb(str1, str2);
}

int main() {
  func([](std::string arg1, std::string arg2){
      std::cout << "call callback func" << std::endl;
      std::cout << "arg1: " << arg1 << std::endl;
      std::cout << "arg2: " << arg2 << std::endl;
    });
  // use default parameters
  func();
  return 0;
}