Help on uninitialised values

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

Hi monks,

I'm getting the error "Use of uninitialised values..." from the following code:

my %hash = @_;

$hash{'from'} ||= 0;

if ($hash{'from'} eq 'main') {
   # code
}
[download]

There's probabaly something wrong there but I can't figure out what. How do I modify the code to rid the error message?

Thanks in advance :)

Update:Thanks to all. My apolgoies, the above snippet isn't the culprit, I'll look at other parts of the code to pinpoint where the error comes from. Will post the result here.

Comment on Help on uninitialised values Download Code

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Re: Help on uninitialised values by davido (Cardinal) on Jul 28, 2004 at 15:45 UTC
I have tested the code with a variety of possibilities for @_, and can't find any combination that causes the code posted to report "Use of uninitialized values". There must be something else going on we're not seeing. Dave	[reply]
Re^2: Help on uninitialised values by kiat (Vicar) on Jul 28, 2004 at 15:51 UTC
Thanks, davido :) The error log lists several lines of that errors: Use of uninitialised values at Mymodule.pm line 771. On my editor, I did a go to line 771 and couldn't find anything suspicious. The only piece of code that could trigger that error in the region of line 711 is the snippet I gave. I'll examine the code around line 711 in more detai...	[reply]
Re: Help on uninitialised values by Aristotle (Chancellor) on Jul 28, 2004 at 16:17 UTC
The code you posted as is can never lead to that warning. Makeshifts last the longest.	[reply]
Re: Help on uninitialised values by ccn (Vicar) on Jul 28, 2004 at 15:53 UTC
In the warning message you can see a number of a problem line. It'will be useful if you post this line here.	[reply]
Re: Help on uninitialised values by keszler (Priest) on Jul 28, 2004 at 16:14 UTC
If all else fails, step through the code using 'perl -d:ptkdb myprog.pl'. (requires Devel::ptkdb from http://www.cpan.org or the http://www.activestate.com ppm devel-ptkdb.)	[reply]
Re: Help on uninitialised values by wfsp (Abbot) on Jul 28, 2004 at 15:49 UTC
Compiles and runs ok on winXP/activestate. Are you sure that is the all code you're trying to run?	[reply]
Re^2: Help on uninitialised values by kiat (Vicar) on Jul 28, 2004 at 15:53 UTC
Please read my reply to davido. I'm now trying to examine the code for the possible source of that error. Thanks :)	[reply]
Re: Help on uninitialised values by shemp (Deacon) on Jul 28, 2004 at 15:50 UTC
are you positive that the warning is coming from whats posted, or from the section of #code ?	[reply]