Initialize const char* by concatenating another ch

2020-04-26 02:41发布

问题:

I want to refactor:

const char* arr = 
  "The "
  "quick "
  "brown";

into something like:

const char* quick = "quick ";
const char* arr = 
  "The "
  quick
  "brown";

because the string "quick" is used is many other places. Ideally I need to be able to do this with just const primitive types, so no string. What is the best way to do this?

回答1:

Compiling the comments in the form of an answer:

  1. Use a macro.

    #define QUICK "quick "
    
    char const* arr = "The " QUICK "brown";
    
  2. Use std:string.

    std::string quick = "quick ";
    std::string arr = std::string("The ") + quick + "brown";
    

Working code:

#include <iostream>
#include <string>

#define QUICK "quick "

void test1()
{
   char const* arr = "The " QUICK "brown";
   std::cout << arr << std::endl;
}

void test2()
{
   std::string quick = "quick ";
   std::string arr = std::string("The ") + quick + "brown";
   std::cout << arr << std::endl;
}

int main()
{
   test1();
   test2();
}

Output:

The quick brown
The quick brown