[me]
>  Why not write a short, fast get_first() function for your utils directory and be done with
 it?
>  That could work with sets, mappings, generators, and other containers and iterators.
>  No need to fatten the set/frozenset API for something so trivial and so rarely needed.

Forgot to post the code.  It is short, fast, and easy.  It is explicit about handing the cas
e with an empty input.  And it is 
specific about which value it returns (always the first iterated value; not an arbitrary one
).  There's no guessing about what it 
does.  It gets the job done.

def first(iterable):
    'Return the first value from a container or iterable.  If empty, raises LookupError'
    for value in iterable:
        return value
    raise LookupError('no first value; iterable is empty')

If desired, it is not hard to change to the last time to return a default value or some othe
r exception.


Raymond



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