Add custom messages in assert?

c++ assert
Killrazor picture Killrazor · Sep 12, 2010 · Viewed 71.5k times · Source

Is there a way to add or edit the message thrown by assert? I'd like to use something like 

assert(a == b, "A must be equal to B");

Then, the compiler adds line, time and so on...

Is it possible?

Answer

zneak picture zneak · Sep 12, 2010

A hack I've seen around is to use the && operator. Since a pointer "is true" if it's non-null, you can do the following without altering the condition:

assert(a == b && "A is not equal to B");

Since assert shows the condition that failed, it will display your message too. If it's not enough, you can write your own myAssert function or macro that will display whatever you want.

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