例如创建 RefCounted 的函数 (FOLLY_LIKELY 包装了一下builtin_expect)：#if __GNUC__ #define FOLL...
比如非 const 成员使用[],这会触发 COW,因为无法知晓应用程序是否会对返回的字符做修改。典型的如Legality of COW std::string implementation in C++11中举的例子: std::strings("str");constchar* p = s.data(); {std::strings2(s); (void) s[0];// 触发COW} std::cout << *p <<'\n';// ...
01)使用预处理器#define 如:#define BYTE char //使BYTE成为char的别名,注意后面没有分号 02)使用关键字typedef 如:typedef char byte; //使byte成为char的别名,注意后面有分号 typedef char* byte_pointer; //让byte_pointer成为char指针的别名 03)在定义很多变量时,使用预处理器的方法不适用 如:#define FLOA...
verbatim string literals and normal string literals are two ways to define string content verbatim string take all given characters as-is, including new lines, etc. the only escape sequence in a verbatim string literal is "" to denote an embedded " character string.Format escaping Format strings...
; // Define an array of strings where each element contains a version of the // letter I. (An array of strings is used so you can easily modify this // code example to test additional or different combinations of strings.) string[] threeIs = new string[3]; // LATIN SMALL LETTER ...
; string resultFmt = "Comparison: {0,-28} Location: {1,3}"; // Define a string to search for. // U+00c5 = LATIN CAPITAL LETTER A WITH RING ABOVE string CapitalAWithRing = "\u00c5"; // Define a string to search. // The result of combining the characters LATIN SMALL LETTER...
The C run time actually allows you to provide a function of your own, which it will call when it detects an invalid parameter. Then, in this function, you can log the failure, attach a debugger, or do whatever you like. To enable this, you must first define a function that matches ...
; string resultFmt = "Comparison: {0,-28} Location: {1,3}"; // Define a string to search for. // U+00c5 = LATIN CAPITAL LETTER A WITH RING ABOVE string CapitalAWithRing = "\u00c5"; // Define a string to search. // The result of combining the characters LATIN SMALL LETTER...
operator[] Provides a reference to the character with a specified index in a string. Literals The headers that define basic_string also define the following user-defined literals, which create a string of the specified type from the input parameters. Expand table DeclarationDescription inline strin...
包装了一下builtin_expect)：#if __GNUC__ #define FOLLY_DETAIL_BUILTIN_EXPECT(b, t) (__...