I don't think the topic has drifted.
The point I wanted to make was that a ternary conditional is a viable alternative to introducing a scope (a 3-line if), if statement modifiers are not favoured by local shop practices. (Which is a reasonable edict, even if I don't agree with it myself).
I'm not sure where you saw the explicit undef?
There was none. It came about in my snippet from employing a ternary, which requires one to put something "in the else" part.
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