Exception handling - try Catch Method

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
I would like to open a file and if can not open, need to throw a message using Exception handling method(try-catch method).
How can i do that? I have written like this in normal method, how can i convert it try-catch method?

open (FH, "directory/myfile") || die "Can Not open the file";
@array = <FH>;
close(FH);
[download]

Can anyone post a solution here
Regards,
San

Comment on Exception handling - try Catch Method Download Code

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Re: Exception handling - try Catch Method by Zaxo (Archbishop) on Aug 27, 2004 at 03:02 UTC
`use Errno; OPEN: eval { open FH, '<', 'directory/myfile' or die $!; }; if ($@) { { $@ == EACCES and die $@; $@ == ENFILE and sleep(1), goto OPEN; warn $@; } }` [download] There are interesting definitions of try and catch to be seen around the monastery, but they all boil down to the construction I show. After Compline, Zaxo	[reply] [d/l]
Re: Exception handling - try Catch Method by csuhockey3 (Curate) on Aug 27, 2004 at 04:14 UTC
Have a look at try/catch (mirror) by pemungkah. Also read this article about Exception Handling in Perl. csuhockey3	[reply]
Re^2: Exception handling - try Catch Method by tachyon (Chancellor) on Aug 27, 2004 at 07:45 UTC
Don't use that syntax until you have read Re: Re2: Learning how to use the Error module by example. Once you have read that you may well decide not to use it due to the inherent issues. cheers tachyon	[reply]
Re: Exception handling - try Catch Method by Rakeswell (Initiate) on Aug 27, 2004 at 05:42 UTC
Try this: `eval {open (FH, "directory/myfile") \|\| die "Can Not open the file ($!) +";}; if ($@){ # handle your exception # maybe check contents of $@ to decide what to do } @array = <FH>; close(FH);` [download]	[reply] [d/l]
Re: Exception handling - try Catch Method by ybiC (Prior) on Aug 27, 2004 at 03:30 UTC
/me asks ignorantly... I've seen try-catch stuff in my Java^(TM) dabblings, but it seems awkwARd and saskwAAtch. Why, pray tell, might one choose to do it this way? cheers, ybiC striving toward Perl Adept (it's pronounced "why-bick")	[reply]
Re^2: Exception handling - try Catch Method by adrianh (Chancellor) on Aug 27, 2004 at 08:39 UTC
See Best Practices for Exception Handling for some reasons.	[reply]
Re: Exception handling - try Catch Method by reneeb (Chaplain) on Aug 27, 2004 at 06:20 UTC
To use the try-catch-method you can use the Error-module: http://search.cpan.org/~uarun/Error-0.15/Error.pm	[reply]
Re^2: Exception handling - try Catch Method by dragonchild (Archbishop) on Aug 27, 2004 at 11:57 UTC
Read Re: Re2: Learning how to use the Error module by example before recommending Error. ------ We are the carpenters and bricklayers of the Information Age. Then there are Damian modules.... sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon.* - flyingmoose I shouldn't have to say this, but any code, unless otherwise stated, is untested	[reply]
Re: Exception handling - try Catch Method by Matts (Deacon) on Aug 28, 2004 at 16:02 UTC
Along with the suggestions here, don't forget to take a look at the Fatal module (run "perldoc Fatal" on the command line) to see how to have open() automatically throw an exception when it fails to open the file. This automates what I consider most of the hard work of exceptions in perl (i.e. actually remembering to throw them!), and also includes useful error text in the exception.	[reply]

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