In that case, you could make either of two changes:

  1. Modify the sanity test to die if the input data is malformed.
  2. Modify the failing code to test for undef before attempting to dereference the hashref.

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 would do both: make the sanity test issue a warning (with file line number) and then return undef; and add a test for undef before dereferencing.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
In the absence of evidence, opinion is indistinguishable from prejudice.
I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!

In reply to Re^3: Can't use an undefined value as a HASH reference by BrowserUk
in thread Can't use an undefined value as a HASH reference by Anonymous Monk

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