besides using deprecated syntax – "if (defined %hash)" (or "if (defined
@array)" for that matter) – just using "if (%hash)" (or "if (@array)")
would do, it is also unnecessary to create the hash if it doesn't exist
(autovivification will take care of that)

Change-Id: Ib5704b2d609ae3658f3c166f9e26a051957149f8