With arrays taken care of by the first rule, the second rule makes sure that all the standard containers as well as all the user-defined ones that follow the standard sequence interface will work with range-basedforout of the box. For example, in ODB (an ORM for C++), we have the co...
Range-based for loop 在范围上执行for循环。 用作更易读的,相当于传统的用于循环操作范围内的值,例如容器中的所有元素。 句法 attr(optional) for ( range_declaration : range_expression ) loop_statement attr - any number of attributes range_declaration - a declaration of a named variable, ...
http://en.cppreference.com/w/cpp/language/range-for 语法: for (range_declaration:range_expression)loop_statement for (一个变量名 : 可迭代范围) { //循环语句 } 变量名的类型可以是:容器元素的类型,容器元素的引用类型,auto { auto && __range =range_expression; for (auto __begin =begin_expr,...
for(inti:{1,2,3})inti=1;// error: redeclaration Temporary range initializer Ifrange-initializerreturns a temporary, its lifetime is extended until the end of the loop, as indicated by binding to the forwarding reference/* range */.
C++11 引入了 range-based for loop,作为对旧有遍历方式的扩展和简化,旨在提高代码的可读性和安全性。 3. 说明 [-wc++11-extensions] 编译器标志的含义 -Wc++11-extensions 是GCC 编译器的一个警告标志,用于提示代码中使用了 C++11 的扩展特性。当你在编译 C++ 代码时,如果启用了这个警告标志,并且代码中使用...
直觉上`c`的类型应该是`const char&`,但是怎么推理得到`c`的类型呢?细究起来确实花了一番功夫。 使用auto声明的变量必须要给初始值,而这里的语法没有给初始值。Range-Based for loop应该是一种语法糖,实际上编译器应该是当成普通的for循环来处理的。
很多语言都有Range-based for loops这个功能,现在C++终于知道把这个重要功能加进语法中了。这个功能实在不知道该怎么翻译,语文没有学到家。 基本语法 AI检测代码解析 for ( range_declaration : range_expression) loop_statement 1. 比如说: AI检测代码解析 ...
The range-based for loop follows this general format:for( declaration : expression) { //do some loop stuff } C++ CopyHere’s an simple example which prints all the elements in a std::vector:std::vector<int> v1 = {-1, 3, 5, -8, 0}; std::cout << std::endl << "v1: " <...
Finally, C++ has the same concept; you can provide a container to your for loop, and it will iterate over it. We've already seen a few basic examples in What is C++11? To refresh your memory, the range-based for loop looks like this: ...
Range-Based for loop应该是一种语法糖,实际上编译器应该是当成普通的for循环来处理的。 从cppreference(en.cppreference.com/w/c)上可以得到印证。 Range-Based for loop的一般形式(省略了不相关的部分)实际上等价于下面的for循环 for ( item-declaration : range-initializer ) statement item-declaration - a...