I have a simple checking function which i am having trouble with and cannot find the solution. I am basically checking to see if an array has any content. The following code works: 
my @modifiedFiles   = ();  


#assuming that this array is empty
if (!@modifiedFiles) 
{ 
   exit;
}

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The follwoing code does not work and gives the error: 

my $modifiedFiles   = {};  

#assuming this array is empty
if(!$modifiedFiles->{$streamID}}) 
{ 
    print "EXIT";
    exit; 
};

ERROR: Can't use an undefined value as an ARRAY reference at E:\Inetpu
+b\cgi-bin\wms.pl line 163.

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THis is quite an obvious error since $modifiedFiles->{$streamID} has no value. Is there however a function i can use to check wether this array exists at all without throwing up an error like this?

costas

In reply to Simple array checking? by costas

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