Re: VC++2008 and vector exception - not caught

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
microsoft.public.vc.language
Date:
Sun, 20 Jul 2008 01:39:39 +0200
Message-ID:
<A8ednbJjN67Z5h_VnZ2dnUVZ_sudnZ2d@posted.comnet>
* Frank S:

    
With some test code similar to that below, I can't seem to catch the
exception that is thrown on the v1[44]... line.


You're not guaranteed that there will be an exception, just Undefined Behavior
(which might do anything or nothing).

What should I check to solve this problem? (I am using a mixture of MFC
and STL.)


As I recall there is, as you imply, a Visual C++ option to get automatic
checking also for operator[] -- if so then it's presumably documented.

However, why don't you instead make that explicit in the code, and write

   v.at(44) = 22;

Then, for a standard-conforming compiler, you get a std::something exception
derived from std::exception.

    vector<int> v1;
    try
    {
        v1[44] = 22;
    }
    catch(std::exception e)


For efficiency, safety, and not the least not making other programmers waste
time on figuring out "why did he do /that/", consider catching in the idiomatic
way, by reference to const:

   catch( std::exception const& e )

    {
        e.what();
        e.what();
    }


Cheers, & hth.,

- Alf

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