The most likely answer is that defined returns an empty string as a false value. An empty string is defined so the left most defined sees a defined value - the result from the right most defined.

So, not really a bug, just an interesting edge case.

Premature optimization is the root of all job security

In reply to Re: defined defined -- Bug or "Feature"? by GrandFather
in thread defined defined -- Bug or "Feature"? by roho

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