Re: defined or undef

defined is not meant to be used on arrays and must not be used on arrays in forward-compatible code. It doesn't do anything meaningful.

There's some uncertainty as to what you are trying to do.

Are you trying to return a list (0 or more items)? If so, you probably want to count the number of elements in the array.
```
print("Number of elements: ", scalar(@rtnVal), "\n");
[download]
```
That will reveal that you do have a bug.
my @rtnVal = undef;
should be
my @rtnVal = ();
or just
my @rtnVal = undef;
Are you trying to return a scalar (1 item or undefined)? If so, you shouldn't be using an array. In fact, your code actually behaves as if @rtnVal is a scalar. If you change it to a scalar $rtnVal, you should get the results you were expecting.

Update: Added second bullet.

Comment on Re: defined or undef Select or Download Code

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Re^2: defined or undef by Fletch (Bishop) on Oct 30, 2007 at 14:57 UTC
Not to mention if you'd enabled warnings you would have gotten griped at for trying to do so: `$ perl -e 'use warnings; my @bar; print "foo" if defined @bar' defined(@array) is deprecated at -e line 1. (Maybe you should just omit the defined()?)` [download] We're looking for a Perl and Database Developer for Corporate Investments Group. </p;	[reply] [d/l]
Re^2: defined or undef by kevind0718 (Scribe) on Oct 30, 2007 at 15:18 UTC
I am attempting to return a list, because getElementsByTagName retruns a list. In this case the list sould contain one item. my @rtnVal = undef; is adding an undefined element to the @rtnVal array? Oh my. Not what I expected. Is this valid code print ( @rtnVal ? " defined \n" : " undefined \n" ); Please take a look at your suggested code. I do believe that your second suggestion is what I have. thanks for your quick reply. kd	[reply]
Re^3: defined or undef by ikegami (Patriarch) on Oct 30, 2007 at 15:20 UTC
Undefined is a special scalar value. It makes no sense to call an array undefined, so that should read `print ( @rtnVal ? " not empty \n" : " empty \n" );` Whether `getElementsByTagName` returns an list or not is irrelevant. I was asking what did you want `getCBLValue` to return.	[reply] [d/l] [select]
Re^4: defined or undef by kevind0718 (Scribe) on Oct 30, 2007 at 15:49 UTC
as you suggested I have been using print ( @rtnVal ? " not empty \n" : " empty \n" ); in many places. I expect getCBLValue to return a list. Maybe I should declare @rtnVal as follows: my @rtnVal ; And see what happens. kd	[reply]
Re^5: defined or undef by kevind0718 (Scribe) on Oct 30, 2007 at 15:56 UTC