you can do the following to see if a var is defined: 
my $var_val;
if(defined($var_val)){
  print "defined";
}
else{
  print "undefined":
}

[download]
this case would pring undefined. if you had 
my $var_val = 'something';

[download]
it would have printed: defined

In reply to Re: Check to see if a variable exists by bear0053
in thread Check to see if a variable exists by Anonymous Monk

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