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From: Francois Berenger <berenger@riken.jp>
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Subject: Re: [Caml-list] How much optimized is the 'a option type ?

On 01/19/2014 03:19 PM, oleg@okmij.org wrote:
>> let rec iter_stream f s =
>>      match (try Some (MyStream.get s) with End_of_stream -> None) with
>>      | None -> ()
>>      | Some (x, s') ->
>>          f x;
>>          iter_stream f s'
>>
>> where an option is used to keep the function tail-rec (I've heard
>> several people tell me they often need to use this), or other cases
>> like optional parameters (which are not going to move to Either),
>> would be useful and future-proof.
>
> I concur this is a very common pattern.

Almost the whole List module in batteries is written in this style,
to avoid reverting lists but keeping tail-rec functions which are not
when implemented naively.