catching exceptions

[Samuele Armondi]

Hi everyone,
I vaguely recall someone mentioning that exceptions should be caught as
const in order to avoid unnecessary copying, i.e.
try
{
// blah
}
catch (const exception e)
{
//deal with it
}
Is this the case? If so, why does const stop the object from being copied?
Thanks in advance,
S. Armondi

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[Victor Bazarov]

"Samuele Armondi" <sa****************@hotmail.com> wrote...

I vaguely recall someone mentioning that exceptions should be caught as
const in order to avoid unnecessary copying, i.e.
try
{
// blah
}
catch (const exception e)
{
//deal with it
}
Is this the case? If so, why does const stop the object from being copied?

It doesn't. You probably want them to be caught by reference:

catch (const exception & e)
{
// deal with it
}

Victor

[Samuele Armondi]

"Victor Bazarov" <v.********@attAbi.com> wrote in message
news:vg************@corp.supernews.com...

"Samuele Armondi" <sa****************@hotmail.com> wrote...

I vaguely recall someone mentioning that exceptions should be caught as
const in order to avoid unnecessary copying, i.e.
try
{
// blah
}
catch (const exception e)
{
//deal with it
}
Is this the case? If so, why does const stop the object from being

copied?
It doesn't. You probably want them to be caught by reference:

catch (const exception & e)
{
// deal with it
}

Victor

Ok, thanks for the info. I probably just misread it!

[Ron Natalie]

"Samuele Armondi" <sa****************@hotmail.com> wrote in message news:3f**********@mk-nntp-1.news.uk.worldonline.com...

Hi everyone,
I vaguely recall someone mentioning that exceptions should be caught as
const in order to avoid unnecessary copying, i.e.
try
{
// blah
}
catch (const exception e)
{
//deal with it
}

Not const, but reference (which may also be const).

catch(exception& e) { ...