Do while 宏
Webdo-while (PHP 4, PHP 5, PHP 7, PHP 8) do-while loops are very similar to while loops, except the truth expression is checked at the end of each iteration instead of in the beginning. The main difference from regular while loops is that the first iteration of a do-while loop is guaranteed to run (the truth expression is only checked at the end of the … Web在Java中,while循环是先判断循环条件,再执行循环。而另一种do while循环则是先执行循环,再判断条件,条件满足时继续循环,条件不满足时退出。它的用法是: do { 执行循环语句 } while (条件表达式); 可见,do while循环会至少循环一次。 我们把对1到100的求和用do while循环改写一下:
Do while 宏
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WebJun 6, 2016 · 没错,do...while (0)的第三个好处就是相当于在宏定义中有一个block (代码块)来盛放大段代码,形成一个语法单元,不会造成上下文混淆,调用时候看起来更像函数调 … WebFeb 19, 2014 · 宏的简单应用很容易掌握,今天主要总结一下宏的特殊符号及惯用法。. (1)宏中包含特殊符号:#、##. (2)宏定义用do { }while (0) 2、特殊符号#、##. …
WebThis happens because a function (like `block_on`) attempted to block the current thread while the thread is being used to drive asynchronous tasks. thread ' tests:: test_sync_method ' panicked at ' Cannot start a runtime from within a runtime. This happens because a function ... 当select!宏 展开时,所有 ... WebIn most computer programming languages a do while loop is a control flow statement that executes a block of code and then either repeats the block or exits the loop depending on a given boolean condition.. The do while construct consists of a process symbol and a condition. First the code within the block is executed. Then the condition is evaluated. If …
WebJun 24, 2024 · 宏被展开后,上面的调用语句会保留初始的语义,同时绝大部分编译器都能够识别do{...}while(0)这种无用的循环并进行优化,不会导致性能优化的降低。. 小结. 在Linux内核和驱动代码还有cocos2d-x中,很多宏实现都使用do{...}while(0)来包裹他们的逻辑,Google的Robert Love(先前从事Linux内核开发)给我们解答 ... Web在do和while之間給出的代碼將被執行,直到條件(condition)成爲true。 在do-while循環中,語句在條件之前給出,所以語句或代碼將至少有一次執行。換句話說,我們可以說do-while循環執行語句一次或多次。 如果你希望至少執行一次代碼,使用do-while循環是最好不 …
WebJun 24, 2024 · 宏被展开后,上面的调用语句会保留初始的语义,同时绝大部分编译器都能够识别do{...}while(0)这种无用的循环并进行优化,不会导致性能优化的降低。. 小结. …
WebThe do..while loop is similar to the while loop with one important difference. The body of do...while loop is executed at least once. Only then, the test expression is evaluated. … half round hanging basketsWebJan 17, 2024 · 在嵌入式开发的过程中,我们经常可以看到在一些优秀开源代码的头文件里发现一些宏定义使用了do{}while(0)语句,也许你会疑惑do{}while(0)不就是只执行一次 … half round industrial sinkWebThe syntax of a do...while loop in C programming language is −. do { statement (s); } while ( condition ); Notice that the conditional expression appears at the end of the loop, so the … half round hanging flower potsWebThe do..while loop is similar to the while loop with one important difference. The body of do...while loop is executed at least once. Only then, the test expression is evaluated. The syntax of the do...while loop is: do { // the body of the loop } while (testExpression); half round hanging basketWeb在C++中, do...while 通常是用来做循环用的,然而我们做循环操作可能用for和while要多一些。经常看到一些开源代码会出现do...while(0)这样的代码,这样的代码看上去肯定不是用来做循环的,那为什么要这样用呢? ... 辅助定义复杂的宏,避免引用的时候出错,提高 ... half round hallway tablesWebwhile 문은 조건식이 '참'인 경우 계속해서 괄호 안의 내용을 반복 수행 하는 반복문이랍니다. 위 코드를 보면 정수 i의 초기값을 1로 초기화 하였고, 합계를 저장할 변수를 sum으로 하고, … half round indoor matWebApr 10, 2024 · c语言定义宏的时候使用do while. 在 C 语言中,使用 do-while 结构来定义宏时,通常是为了确保宏定义中的代码块在使用时可以像一个独立的语句一样被执行。. 这里的 do { ... } while (0) 实际上是一个包含单个语句的循环结构。. 这个循环结构的主体部分就是宏 … half round iron table