All, except the empty set case. Eventually you might need to investigate further to see if one such set was consistant with other information--order and delivery notes etc.--but initially, just whether any such (non-empty) set existed might be a useful boolean. But it would be rendered meaningless if the empty set is considered a match.

In truth, it was just the first example I thought of that supported my argument. However, hard as I might try, I cannot think of a counter example. Not one.

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".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^9: Recursion problem by BrowserUk
in thread Recursion problem by someone202

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