But there is the school of thought termed the robustness principle, that goes Be conservative in what you send, be liberal in what you accept.

I definitely prefer 'Be conservative in what you send, be conservative in what you accept.' I hold the opinion that trying to be liberal with input (especially: trying to fix malformed input) is pretty much guaranteed to lead to a bug somewhere later on.

@OP: Both of the suggestions BrowserUK gave are good. But trying to apply the robustness principle (-> be liberal in what you accept) and automagically initialize a hash reference may sound like a good idea at first but can turn out to be a bad one.

In reply to Re^4: Can't use an undefined value as a HASH reference by Monk::Thomas
in thread Can't use an undefined value as a HASH reference by Anonymous Monk

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