宏assert的用法.txt

里面的代码是自己写的,参考书是thingking in c++,代码有详细的说明,对学习c++语法非常有帮助!

/*本程序对应于P197。
* 本程序是为了说明 assert()宏的用法
*注意点1：when you use assert(),you give it an argument that is an expression
*you are "asserting to be true."the preprocessor generates code that will 
*test the assertion.If the assertion isn't true ,the program will stop after
*issuing an error message telling you what the assertion was and that it
*failed.
*注意点2：When you finished debugging,you can remove the code genereted
* by the macro by placing the line : #define NDEBUG in the program before
*the inclusion of <cassert>.
*/
#include<iostream>
//#define NDEBUG  //参考注意点2的说明
#include<cassert>
using namespace std;

int main()
{
	int i = 100;
	assert(i != 100);   //fails
}