complete enumeration. I'm taking it for granted that the current behavior on Float is useful; I honestly don't see how you could argue with that. People use it all the time; I used it just this morning. Of course it's useful.
It was useful but not as useful as a 'range' function. I thought it was quite useful and used it even though I *already knew* about 'last [0, 0.1 .. 2] > 2'. But of course this eventually lead to a tricky bug, followed by a "never again" and witch hunt for all uses of [..] with floats :) Maybe it's just me, but would guess that your students would find it perfectly clear and not confusing at all... until they found out about that little thing with 'last' above... *then* they might be confused. Maybe this is just an argument that Double's enumFromThenTo should use multiplication instead of successive addition?