On Wed, Sep 21, 2011 at 14:31, Casey McCann <cam@uptoisomorphism.net> wrote:

My thoughts are that the first interpretation is most naturally suited
to list range syntax, that the second would be better served by a
slightly different syntax to make the predicate more explicit, and
that the third bugs the crap out of me because it's really very useful
but I can't think of a concise and unambiguous syntax for it.

Based on what you said, I'm wondering if the first gets basic fromTo syntax, the third gets fromThenTo syntax, and the second strikes me as a simplified form of list comprehension and might possibly be phrased as a cross between range and comprehension. Although the most "correct" such cross has an ambiguity with the comma... can we still use | as the delimiter, read as "such that"? ([a .. z | filter])

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