in reply to use XML::DOM - what to do with empty tags?

If it's throwing an error, then in addition to the if statements, you should perhaps trap the potential errors in an eval block: 
# declare lexical variable *outside the scope of the eval*
my $BusUrl;

# trap potential error
eval {
  $BusUrl = $contact->getElementsByTagName( "BusinessUrl" );
};
# check if tag retrieval failed
if($@) {
  # assign an empty (but defined) string
  $BusUrl = '';
}

$bus_url = $BusUrl->item( 0 )->getChildAtIndex( 0 )->getData();

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The trouble with having an open mind, of course, is that people will insist on coming along and trying to put things in it.
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Re^2: use XML::DOM - what to do with empty tags?
by kevyt (Scribe) on Jan 03, 2007 at 16:48 UTC
    Thanks, That makes a lot of sense. I am still getting the error: 
    Can't call method "getData" on an undefined value at parse_xml.pl line
+ 87.

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    New code: 
    my $Long = $contact->getElementsByTagName( "Longitude" );
my $long = $Long->item(0)->getChildAtIndex(0)->getData();

# declare lexical variable *outside the scope of the eval*
my $BusUrl;

# trap potential error
eval {
   $BusUrl = $contact->getElementsByTagName( "BusinessUrl" );
};

# check if tag retrieval failed
if($@) {
   # assign an empty (but defined) string
   #$BusUrl = '';
}

$bus_url = $BusUrl->item(0)->getChildAtIndex(0)->getData(); # line 87

# change phone number format

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      ah, the example code I provided just assigns an empty string to $BusUrl, which you later use as an object (my bad). so really, what you'd want to do is something like this: 
      if($@) {
  # assign an empty (but defined) string to $bus_url
  $bus_url = '';
}
else {
  # assign tag contents to $bus_url
  $bus_url = $BusUrl->item(0)->getChildAtIndex(0)->getData(); 
}

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       what you really want to do is follow mirod's advice and use the hasChildNodes method (note that he uses a much more flexible implementation than the following): 
      my $BusUrl = $contact->getElementsByTagName( "BusinessUrl" );

# check if tag is defined and has children
if (defined $BusUrl && $BusUrl->hasChildNodes) {
  $bus_url = $BusUrl->item( 0 )->getChildAtIndex( 0 )->getData();
}
# otherwise assign an empty string
else {
  $bus_url = '';
}

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      __________
      The trouble with having an open mind, of course, is that people will insist on coming along and trying to put things in it.
      - Terry Pratchett

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