which re a|l|t|e|r|n|a|t|i|v|e matched?

[Skip Montanaro]

    >> pat = reduce(lambda acc, key: "%s|(%s)" % (acc, key), d.keys())[1:]

    Diez> Oops, forgot the first argument for acc, its "" of course:

    Diez> pat = reduce(lambda acc, key: "%s|(%s)" % (acc, key), d.keys(), "")[1:]

Don't say, "of course".  I would rather stick my hand in a vise than use
reduce() so it wasn't obvious to me. ;-)  Thanks for the suggestion.  I
suspect Tim's .lastindex solution will be simplest.

Skip