PHP/Data Type/empty

bool empty ( mixed var ) returns true if its parameter has a false value

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$var1 = "0";

   $var2 = "1";
   $var3 = "";
   if (empty($var1)) print "Var1 empty\n";
   if (empty($var2)) print "Var2 empty\n";
   if (empty($var3)) print "Var3 empty\n";
   if (empty($var4)) print "Var4 empty\n";
 
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