my @array=qw/foo bar/;
$array[3] = "baz";

foo1( @array );  # $array[2] is undefined
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One way to avoid the warning would be:

   for my $param (grep {defined} @_) {
      for my $val ( split /\n/, $param ) {
         print "The value is: $val\n";  # or whatever you want to do
      }
   }
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The other methods suggested above would also work, I expect. There might be reasons for preferring one approach over the other, depending on the rest of your application.

Reply most helpful. I was able to make the proper tests, and incorporate the detection of "undefined" stuff in my code.

Sorry if the example isn't that good. I tried to extract the pertinant stuff for the example. The intended application is a "tie" method for output (prints). It replaces the output method to stdout, and adds the time, and module/line as a prefix. It seems to work quite well, as we've put it in a bunch of scripts here. Efficient? I don't know, it does the job, and really isn't called that much. I suspect that being my first module, it refelcts my background ("...you can program in Fortran in any language.").

Your line eight should be something like,

    @vals = split /(\n)/, $_;
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I don't understand what the "fool" routine is. You have a very straightforward loop, done in C-style. Perhaps if you included some of the Tie code?

This use of while doesn't seem to set $_ for me. Which version of Perl are you using?

I was thinking of while (<$fh>) { }, which does.

After Compline,
Zaxo

I'd be similarly "enlightened" if I could see a real example--a small complete example--that I could just run to see the error message. So please bear with me, as my ESP::Clairvoyance module doesn't compile at the moment.

If I had to guess, (and I do must!), I'd suspect that shift is returning an undef when it runs out of items, and that is the source of your error...

UPDATE: perhaps changing

    @vals = split /(\n)/, (shift); # Error happens here
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    @vals = split /(\n)/, (shift)||'';
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UPDATE: As ikegami states below, my attempted "fix" is quite bogus. Luckily, he also had a better suggestion. (Had I refreshed before posting my prior update, I'd've probably been spared the embarassment! Thanks Icky! 8^)

--roboticus

||'' obliterates 0. Use defined to check if something defined (as in this earlier post).

If you have 'some weird error', the problem is probably with your frobnitzer. — #11938

:-)