14 lines
363 B
Plaintext
14 lines
363 B
Plaintext
(* There is no undefined value in OCaml,
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but if you really need this you can use the built-in "option" type.
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It is defined like this: type 'a option = None | Some of 'a *)
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let inc = function
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Some n -> Some (n+1)
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| None -> failwith "Undefined argument";;
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inc (Some 0);;
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(* - : value = Some 1 *)
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inc None;;
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(* Exception: Failure "Undefined argument". *)
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