支持彩色代码的c++ 11

是通用的，适用于所有数据类型 类似JavaScript console.log(1，"23") 支持颜色代码的信息，警告，错误。 例子:

#pragma once
#include <iostream>
#include <string>

const std::string RED = "\e[0;91m";
const std::string BLUE = "\e[0;96m";
const std::string YELLOW = "\e[0;93m";

class Logger {
private:
  enum class Severity { INFO, WARN, ERROR };

  static void print_colored(const char *log, Severity severity) {
    const char *color_code = nullptr;

    switch (severity) {
    case Severity::INFO:
      color_code = BLUE.c_str();
      break;
    case Severity::WARN:
      color_code = YELLOW.c_str();
      break;
    case Severity::ERROR:
      color_code = RED.c_str();
      break;
    }

    std::cout << "\033" << color_code << log << "\033[0m -- ";
  }

  template <class Args> static void print_args(Args args) {
    std::cout << args << " ";
  }

public:
  template <class... Args> static void info(Args &&...args) {
    print_colored("[INFO] ", Severity::INFO);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }

  template <class... Args> static void warn(Args &&...args) {
    print_colored("[WARN] ", Severity::WARN);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }

  template <class... Args> static void error(Args &&...args) {
    print_colored("[ERROR]", Severity::ERROR);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }
};

可能你想重载或默认参数-用默认参数定义相同的函数:

void doStuff( int a, double termstator = 1.0, bool useFlag = true )
{
   // stuff
}

void doStuff( double std_termstator )
{
   // assume the user always wants '1' for the a param
   return doStuff( 1, std_termstator );
}

这将允许你用四种不同的调用之一来调用该方法:

doStuff( 1 );
doStuff( 2, 2.5 );
doStuff( 1, 1.0, false );
doStuff( 6.72 );

…或者你可以从C中寻找v_args调用约定。

// spawn: allocate and initialize (a simple function)
template<typename T>
T * spawn(size_t n, ...){
  T * arr = new T[n];
  va_list ap;
  va_start(ap, n);
  for (size_t i = 0; i < n; i++)
    T[i] = va_arg(ap,T);
  return arr;
}

用户写道:

auto arr = spawn<float> (3, 0.1,0.2,0.3);

从语义上讲，这看起来和感觉上完全像一个n参数函数。在引擎盖下，你可能会以这样或那样的方式打开它。

正如其他人所说，c风格的变量。但是你也可以对默认参数做类似的事情。

如果所有实参都是const且类型相同，也可以使用initializer_list

支持彩色代码的c++ 11

是通用的，适用于所有数据类型 类似JavaScript console.log(1，"23") 支持颜色代码的信息，警告，错误。 例子:

#pragma once
#include <iostream>
#include <string>

const std::string RED = "\e[0;91m";
const std::string BLUE = "\e[0;96m";
const std::string YELLOW = "\e[0;93m";

class Logger {
private:
  enum class Severity { INFO, WARN, ERROR };

  static void print_colored(const char *log, Severity severity) {
    const char *color_code = nullptr;

    switch (severity) {
    case Severity::INFO:
      color_code = BLUE.c_str();
      break;
    case Severity::WARN:
      color_code = YELLOW.c_str();
      break;
    case Severity::ERROR:
      color_code = RED.c_str();
      break;
    }

    std::cout << "\033" << color_code << log << "\033[0m -- ";
  }

  template <class Args> static void print_args(Args args) {
    std::cout << args << " ";
  }

public:
  template <class... Args> static void info(Args &&...args) {
    print_colored("[INFO] ", Severity::INFO);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }

  template <class... Args> static void warn(Args &&...args) {
    print_colored("[WARN] ", Severity::WARN);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }

  template <class... Args> static void error(Args &&...args) {
    print_colored("[ERROR]", Severity::ERROR);
    int dummy[] = {0, ((void)print_args(std::forward<Args>(args)), 0)...};
    std::cout << std::endl;
  }
};