Re: How to use assert?

From:

"Leigh Johnston" <leigh@i42.co.uk>

Newsgroups:

comp.lang.c++

Date:

Thu, 13 May 2010 19:38:36 +0100

Message-ID:

<As2dnZyHOfS22nHWnZ2dnUVZ8uCdnZ2d@giganews.com>

"none" <""mort\"@(none)"> wrote in message
news:4bec4611$0$278$14726298@news.sunsite.dk...

Leigh Johnston wrote:

"none" <""mort\"@(none)"> wrote in message
news:4bec3ae6$0$286$14726298@news.sunsite.dk...

I am trying to use assert to test an expression:

#include <assert.h>
#include <vector>

int main() {
  std::vector<int> myVector;
  myVector.push_back(3);
  assert (myVector[0] == 444);
}

when I run this code I get no fail message. Should assert not report an
error when the expression evaluates to false?

assert does nothing if NDEBUG is defined, try running a debug build of
your program rather than a release build.

/Leigh

Hm my debug build takes forever to compile and run so I am currently
developing on a release build. Is it not possible to undefine NDEBUG in my
release code?

Your compiler should allow you to configure pre-processor settings such as
what symbols are defined. Failing that:

#undef NDEBUG

You should make sure however that you really need a release mode assert:
consider throwing an exception instead. I primarily use assert as a
debugging aid rather than as some error report to end-users.

/Leigh