see #12: translate ch06

code/6/6.1.cpp

@@ -3,8 +3,9 @@
 // modern c++ tutorial
 //
 // created by changkun at changkun.de
+// https://github.com/changkun/modern-cpp-tutorial
 //
-// 正则表达式库
+// Regular Expression
 
 #include <iostream>
 #include <string>
@@ -12,7 +13,9 @@
 
 int main() {
     std::string fnames[] = {"foo.txt", "bar.txt", "test", "a0.txt", "AAA.txt"};
-    // 在 C++ 中 `\` 会被作为字符串内的转义符，为使 `\.` 作为正则表达式传递进去生效，需要对 `\` 进行二次转义，从而有 `\\.`
+    // In C++, `\` will be used as an escape character in the string. 
+    // In order for `\.` to be passed as a regular expression, 
+    // it is necessary to perform second escaping of `\`, thus we have `\\.`
     std::regex txt_regex("[a-z]+\\.txt");
     for (const auto &fname: fnames)
         std::cout << fname << ": " << std::regex_match(fname, txt_regex) << std::endl;
@@ -21,8 +24,8 @@ int main() {
     std::smatch base_match;
     for(const auto &fname: fnames) {
         if (std::regex_match(fname, base_match, base_regex)) {
-            // sub_match 的第一个元素匹配整个字符串
-            // sub_match 的第二个元素匹配了第一个括号表达式
+            // the first element of std::smatch matches the entire string
+            // the second element of std::smatch matches the first expression with brackets
             if (base_match.size() == 2) {
                 std::string base = base_match[1].str();
                 std::cout << "sub-match[0]: " << base_match[0].str() << std::endl;