note that if there are duplicate entries in the array, the index of the first (lowest index) entry will be returned. eliminate the reverse call to have it the other way.
This should be restated to say exactly two duplicate entries. A third or further duplicates would be undetectable with this method.

In reply to Re^2: Finding index of an entry in an Array by jrsimmon
in thread Finding index of an entry in an Array by monkfan

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