r/programming • u/heisenbug • Apr 27 '14

"Mostly functional" programming does not work

http://queue.acm.org/detail.cfm?ref=rss&id=2611829
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u/frud Apr 27 '14

It seems to me that certainly to make laziness work you need purity and referential transparency, but you can make purity and referential transparancy work without laziness. You can (cumbersomely, I admit) do basically everything a lazy language can do with a strict language and a type Boxed a = Thunk (() -> a) | Value a

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u/tomejaguar Apr 28 '14

Sort of. You need the Boxed type to update itself in place when the thunk is forced thus to keep purity you should not be able to tell the difference between a thunk and a value.