Regex

#include <iostream>#include <cassert>#include <string>#include "boost/regex.hpp"//完全匹配void boostregex_match(void);//部分数据可以匹配void boostregex_search(void);//替换void boostregex_replace(void);//关于重复和贪婪void Test1(void);//regex_iteratorvoid Test2(void);//regex_token_iterator void Test3(void);int main() { //boostregex_search();//boostregex_replace();//Test1();//Test2();Test3();return 0;}void boostregex_match(void){// 3 digits, a word, any character, 2 digits or "N/A",   // a space, then the first word again //用于表示"3个数字, 一个单词, 任意字符, 2个数字或字符串"N/A," 一个空格, 然后重复第一个单词."：boost::regex reg("\\d{3}([a-zA-Z]+).(\\d{2}|N/A)\\s\\1");std::string correct = "123Hello N/A Hello";std::string incorrect = "123Hello 12 hello";assert(boost::regex_match(correct, reg) == true);assert(boost::regex_match(incorrect, reg) == false);return;}//部分数据可以匹配void boostregex_search(void){// "new" and "delete" 出现的次数是否一样？ boost::regex reg("(new)|(delete)"); boost::smatch m;  std::string s=    "Calls to new must be followed by delete. \     Calling simply new results in a leak!";  int new_counter=0; int delete_counter=0; std::string::const_iterator it=s.begin();  std::string::const_iterator end=s.end();  while (boost::regex_search(it,end,m,reg)) {    // 是 new 还是 delete?  m[1].matched ? ++new_counter : ++delete_counter; it=m[0].second; } if (new_counter!=delete_counter) std::cout << "Leak detected!\n";  else    std::cout << "Seems ok...\n";return;/*Leak detected!请按任意键继续. . .*/}//替换void boostregex_replace(void){boost::regex reg("(Colo)(u)(r)", boost::regex::icase | boost::regex::perl);  std::string s = "Colour, colours, color, colourize";  s = boost::regex_replace(s, reg, "$1$3");  std::cout << s;return;/*Color, colors, color, colorize请按任意键继续. . .*/}//关于重复和贪婪void Test1(void){boost::regex reg("(.*)(\\d{2})");  boost::cmatch m;  const char* text = "Note that I'm 31 years old, not 32.";  if (boost::regex_search(text, m, reg)) {if (m[1].matched)      std::cout << "(.*) matched: " << m[1].str() << '\n';   if (m[2].matched)      std::cout << "Found the age: " << m[2] << '\n'; }return;/*(.*) matched: Note that I'm 31 years old, notFound the age: 32请按任意键继续. . .*/}class regex_callback { int sum_; public: regex_callback() : sum_(0) {}  template <typename T> void operator()(const T& what) {sum_ += atoi(what[1].str().c_str()); }  int sum() const { return sum_; }};//regex_iteratorvoid Test2(void){boost::regex reg("(\\d+),?");  std::string s = "1,1,2,3,5,8,13,21";  boost::sregex_iterator it(s.begin(), s.end(), reg);  boost::sregex_iterator end;  regex_callback c;  int sum = for_each(it, end, c).sum();return;}//regex_token_iterator void Test3(void){boost::regex reg("/");  std::string s = "Split/Values/Separated/By/Slashes,"; std::vector<std::string> vec;  boost::sregex_token_iterator it(s.begin(), s.end(), reg, -1);  boost::sregex_token_iterator end;  while (it != end)    vec.push_back(*it++); assert(vec.size() == std::count(s.begin(), s.end(), '/') + 1);  assert(vec[0] == "Split");return;}