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Use of uninitialized value in concatenation (.) or string at reflectio
+ns.cgi line 15 (#1) (W uninitialized) An undefined value was used as
+if it were already defined. It was interpreted as a "" or a 0, but ma
+ybe it was a mistake. To suppress this warning assign a defined value
+ to your variables. To help you figure out what was undefined, perl t
+ells you what operation you used the undefined value in. Note, howeve
+r, that perl optimizes your program and the operation displayed in th
+e warning may not necessarily appear literally in your program. For e
+xample, "that $foo" is usually optimized into "that " . $foo, and the
+ warning will refer to the concatenation (.) operator, even though th
+ere is no . in your program.