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[Caml-list] mystified by typing of optional arguments
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Date: -- (:)
From: Francois Rouaix <francois@r...>
Subject: [Caml-list] mystified by typing of optional arguments
Hi all,
The following example mystifies me

let f ?opt x =
   match opt with
   | None -> x
   | Some dx -> x + dx

let g x = x + 1


let h1 = function
   | 0 -> [g]
   | _ -> [f; g]


let h2 = function
   | _ -> [f; g]


h1 is typable but not h2.
Why is that ?

--f
PS: the example code is not meant to be useful in any way other than 
reproducing the behavior of type checking.

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