[Python-ideas] Re: Argumenting in favor of first()

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Does that mean that first() and next() are undefined for sets?

[Stephen J. Turnbull <turnbull.stephen.fw@u.tsukuba.ac.jp>]

first() is undefined. next() is defined by reference to iterating over the set (that's why I don't have a problem with iterating over a set).

Every suggestion here so far has satisfied that, if S is a non-empty set, assert next(iter(S)) is first(S) succeeds. That is, `first()` is _defined_ by reference to iteration order. It's "the first" in that order (hence the name).