c++ - 断言失败时如何打印附加信息？

Question

如果 assert 失败，通常需要打印出附加信息。一种方法是:

assert(vec.size() > i || 
  !(std::cerr << "False: " << vec.size() << ">" << i))

这样，当 assert 失败时会打印出实际尺寸。但它很丑，而且很容易忘记 ! ，这会使断言条件为真，程序将继续。

人们改用什么来打印关于断言失败的附加信息，就像上面一样？

Answer 1

#define ASSERT(condition) { if(!(condition)){ std::cerr << "ASSERT FAILED: " << #condition << " @ " << __FILE__ << " (" << __LINE__ << ")" << std::endl; } }

用法:

ASSERT(vec.size()>1);

结果:

ASSERT FAILED: vec.size()>1 @ main.cpp (17)

您可以根据需要选择将 DebugBreak() 或 exit(-1) 或 waterver 放入宏中。

更新了左右分开的宏:

#define ASSERT(left,operator,right) { if(!((left) operator (right))){ std::cerr << "ASSERT FAILED: " << #left << #operator << #right << " @ " << __FILE__ << " (" << __LINE__ << "). " << #left << "=" << (left) << "; " << #right << "=" << (right) << std::endl; } }

用法:

ASSERT(a,>,b);

结果:

ASSERT FAILED: a>b @ assert2.cpp (8). a=3; b=4