Re: [Caml-list] "List.index" or "List.unique" functions?

[Remi Vanicat <remi.vanicat@laposte.net>]

Karl Zilles <zilles@1969.ws> writes:

> Rahul Siddharthan wrote:
>> I have a question: suppose I have a list l1, and I want to create a new
>> list l2 with only one copy of any repeated members of the first list
>> (eg, l1=[1;2;3;4;3;4;5;6;5] -> l2=[1;2;3;4;5;6])
>
> let unique l = List.rev (List.fold_left (fun results x -> if List.mem
> x 		results then results else x::results) [] l);;
>
> unique [1;2;3;4;3;4;5;6;5];;
> - : int list = [1; 2; 3; 4; 5; 6]
>
> List.rev is not tail recursive, so you wouldn't want to use this
> function on industrial size lists.

List.rev is tail recursive...

[...]


-- 
Rémi Vanicat

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