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Date: Fri, 20 Jan 2012 22:09:13 +0100
From: oliver <oliver@first.in-berlin.de>
To: Edgar Friendly <thelema314@gmail.com>
Cc: caml-list@inria.fr
Message-ID: <20120120210913.GA2310@siouxsie>
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Subject: Re: [Caml-list] is there a more concise way to write this?

On Fri, Jan 20, 2012 at 10:04:30PM +0100, oliver wrote:
> 
> My fold approach version:
> 
> let folded (out, value) o v =
>   let a = if out   then Some o else None in
>   let b = if value then Some v else None in
>   List.fold_left ( fun accum elem -> match elem with None -> accum | Some x -> x :: accum ) [] [ b; a ]
> 
> or when following the way the other functions are notated
> (o and v not as parameters but in the environment) so that
> you can paste it into your code:
> 
> 
> let folded_env (out, value) =
>   let a = if out   then Some o else None in
>   let b = if value then Some v else None in
>   List.fold_left ( fun accum elem -> match elem with None -> accum | Some x -> x :: accum ) [] [ b; a ]
> 
> If
>   let ... = ... in  let ... = ...  in ...
> is slower than than 
>   let ... = ... and let ... = ...  in ...
[...]

meanI t:
If
  let ... = ... in  let ... = ...  in ...
is slower than than 
  let ... = ... and ... = ...  in ...

of course.

(copy & paste-related typo)


Ciao,
   Oliver