Re: Doubt in Perl exception handling

From: Jim Gibson (jgibson_at_mail.arc.nasa.gov)
Date: 03/10/05 

Date: Thu, 10 Mar 2005 10:47:09 -0800

In article <1110427745.612099.141330@g14g2000cwa.googlegroups.com>,
Babu <babu.subburathinam@gmail.com> wrote:

> Hi,
> I am a Perl newbie and have a doubt on Perl exception handling.
> My understanding regarding exception handling is execute a piece of
> code, if any exception occurs, handle the exception and proceed as if
> the error never occurred at all.
> So code would look like
>
> Eval {

It's 'eva'. Case matters.

> # do something
> }; if ($@)
> {
> #handle exception
> }
> #procees as if no exception occurred
>
> But in Perl I find that very often we die upon an exception. We never
> try to handle the exception and continue. Is my understanding correct?
> Is this the right way to do it?

The 'right way' to do it depends upon the application. I myself don't
use the eval { } method for trapping exceptions, because almost all of
the Perl programs I write are used by me and noboby else. Most of the
fatal errors in my Perl programs are caused by bad input or unforeseen
circumstances. When I encounter a fatal error, I analyze the cause and
modify my program to handle it.

On the other hand, were I writing programs for a production environment
in which the programs were used by others, I would pay much more
attention to trapping these unforeseen circumstances and dealing with
them somehow.

FYI: this newsgroup is defunct; try comp.lang.perl.misc in the future.

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